v13.0.0-30 -- distribution files

.babelrc

@@ -0,0 +1,12 @@
+{
+  "presets": [
+    ["latest", {
+      "es2015": {
+        "modules": false
+      }
+    }]
+  ],
+  "plugins": [
+    "external-helpers"
+  ]
+}

.flowconfig

@@ -5,6 +5,8 @@
 
 [include]
 ./src/
+./tests-lib/
+./test/
 
 [libs]
 ./declarations/

.gitignore

@@ -1,15 +1,4 @@
 node_modules
 bower_components
-build
-build_test
-.directory
-.codio
-.settings
-.jshintignore
-.jshintrc
-.validate.json
-/y.js
-/y.js.map
-/y-*
-.vscode
-jsconfig.json
+/y.*
+/examples/yjs-dist.js*

.gitmodules

@@ -1,4 +0,0 @@
-[submodule "dist"]
-	path = dist
-	url = https://github.com/y-js/yjs.git
-	branch = dist

README.md

@@ -1,133 +1,216 @@
 
 # ![Yjs](http://y-js.org/images/yjs.png)
 
-Yjs is a framework for optimistic concurrency control and automatic conflict resolution on shared data.
-The framework provides similar functionality as [ShareJs] and [OpenCoweb], but supports peer-to-peer
-communication protocols by default. Yjs was designed to handle concurrent actions on arbitrary data
-like Text, Json, and XML. We also provide support for storing and manipulating your shared data offline.
-For more information and demo applications visit our [homepage](http://y-js.org/).
+Yjs is a framework for offline-first p2p shared editing on structured data like
+text, richtext, json, or XML. It is fairly easy to get started, as Yjs hides
+most of the complexity of concurrent editing. For additional information, demos,
+and tutorials visit [y-js.org](http://y-js.org/).
 
-You can create you own shared types easily.
-Therefore, you can design the structure of your custom type,
-and ensure data validity, while Yjs ensures data consistency (everyone will eventually end up with the same data).
-We already provide abstract data types for
+### Extensions
+Yjs only knows how to resolve conflicts on shared data. You have to choose a ..
+* *Connector* - a communication protocol that propagates changes to the clients
+* *Database* - a database to store your changes
+* one or more *Types* - that represent the shared data
+
+Connectors, Databases, and Types are available as modules that extend Yjs. Here
+is a list of the modules we know of:
+
+##### Connectors
+
+|Name            | Description               |
+|----------------|-----------------------------------|
+|[webrtc](https://github.com/y-js/y-webrtc) | Propagate updates Browser2Browser via WebRTC|
+|[websockets](https://github.com/y-js/y-websockets-client) | Set up [a central server](https://github.com/y-js/y-websockets-client), and connect to it via websockets |
+|[xmpp](https://github.com/y-js/y-xmpp) | Propagate updates in a XMPP multi-user-chat room ([XEP-0045](http://xmpp.org/extensions/xep-0045.html))|
+|[ipfs](https://github.com/ipfs-labs/y-ipfs-connector) | Connector for the [Interplanetary File System](https://ipfs.io/)!|
+|[test](https://github.com/y-js/y-test) | A Connector for testing purposes. It is designed to simulate delays that happen in worst case scenarios|
+
+##### Database adapters
+
+|Name            | Description               |
+|----------------|-----------------------------------|
+|[memory](https://github.com/y-js/y-memory) | In-memory storage. |
+|[indexeddb](https://github.com/y-js/y-indexeddb) | Offline storage for the browser |
+|[leveldb](https://github.com/y-js/y-leveldb) | Persistent storage for node apps |
+
+
+##### Types
 
 | Name     | Description       |
 |----------|-------------------|
 |[map](https://github.com/y-js/y-map) | A shared Map implementation. Maps from text to any stringify-able object |
 |[array](https://github.com/y-js/y-array) | A shared Array implementation |
 |[xml](https://github.com/y-js/y-xml) | An implementation of the DOM. You can create a two way binding to Browser DOM objects |
-|[text](https://github.com/y-js/y-text) | Collaborate on text. Supports two way binding to textareas, input elements, or HTML elements (e.g. <*h1*>, or <*p*>). Also supports the [Ace Editor](https://ace.c9.io) |
+|[text](https://github.com/y-js/y-text) | Collaborate on text. Supports two way binding to the [Ace Editor](https://ace.c9.io), [CodeMirror](https://codemirror.net/), [Monaco](https://github.com/Microsoft/monaco-editor), textareas, input elements, and HTML elements (e.g. <*h1*>, or <*p*>) |
 |[richtext](https://github.com/y-js/y-richtext) | Collaborate on rich text. Supports two way binding to the [Quill Rich Text Editor](http://quilljs.com/)|
 
-Yjs supports P2P message propagation, and is not bound to a specific communication protocol. Therefore, Yjs is extremely scalable and can be used in a wide range of application scenarios.
+##### Other
 
-We support several communication protocols as so called *Connectors*.
-You can create your own connector too - read [this wiki page](https://github.com/y-js/yjs/wiki/Custom-Connectors).
-Currently, we support the following communication protocols:
-
-|Name            | Description               |
-|----------------|-----------------------------------|
-|[xmpp](https://github.com/y-js/y-xmpp) | Propagate updates in a XMPP multi-user-chat room ([XEP-0045](http://xmpp.org/extensions/xep-0045.html))|
-|[webrtc](https://github.com/y-js/y-webrtc) | Propagate updates Browser2Browser via WebRTC|
-|[websockets](https://github.com/y-js/y-websockets-client) | Exchange updates efficiently in the classical client-server model |
-|[test](https://github.com/y-js/y-test) | A Connector for testing purposes. It is designed to simulate delays that happen in worst case scenarios|
-
-You are not limited to use a specific database to store the shared data. We provide the following database adapters:
-
-|Name            | Description               |
-|----------------|-----------------------------------|
-|[memory](https://github.com/y-js/y-memory) | In-memory storage. |
-|[indexeddb](https://github.com/y-js/y-indexeddb) | Offline storage for the browser |
-
-The advantages over similar frameworks are support for
-* .. P2P message propagation and arbitrary communication protocols
-* .. share any type of data. The types provide a convenient interface
-* .. offline support: Changes are stored persistently and only relevant changes are propagated on rejoin
-* .. Intention Preservation: When working on Text, the intention of your changes are preserved. This is particularily important when working offline. Every type has a notion on how we define Intention Preservation on it.
+| Name      | Description       |
+|-----------|-------------------|
+|[y-element](http://y-js.org/y-element/) | Yjs Polymer Element |
 
 ## Use it!
-Install yjs and its modules with [bower](http://bower.io/), or with [npm](https://www.npmjs.org/package/yjs).
+Install Yjs, and its modules with [bower](http://bower.io/), or
+[npm](https://www.npmjs.org/package/yjs).
 
 ### Bower
 ```
-bower install yjs --save
+bower install --save yjs y-array % add all y-* modules you want to use
 ```
-Then you include the libraries directly from the installation folder.
+You only need to include the `y.js` file. Yjs is able to automatically require
+missing modules.  
 ```
 <script src="./bower_components/yjs/y.js"></script>
 ```
 
 ### Npm
 ```
-npm install yjs --save
+npm install --save yjs % add all y-* modules you want to use
 ```
 
-And use it like this with *npm*:
+If you don't include via script tag, you have to explicitly include all modules!
+(Same goes for other module systems)
 ```
-Y = require("yjs");
+var Y = require('yjs')
+require('y-array')(Y) // add the y-array type to Yjs
+require('y-websockets-client')(Y)
+require('y-memory')(Y)
+require('y-array')(Y)
+require('y-map')(Y)
+require('y-text')(Y)
+// ..
+// do the same for all modules you want to use
+```
+
+### ES6 Syntax
+```
+import Y from 'yjs'
+import yArray from 'y-array'
+import yWebsocketsClient from 'y-webrtc'
+import yMemory from 'y-memory'
+import yArray from 'y-array'
+import yMap from 'y-map'
+import yText from 'y-text'
+// ..
+Y.extend(yArray, yWebsocketsClient, yMemory, yArray, yMap, yText /*, .. */)
 ```
 
 # Text editing example
+Install dependencies
 ```
-Y({
-  db: {
-    name: 'memory' // store in memory.
-    // name: 'indexeddb'
-  },
-  connector: {
-    name: 'websockets-client', // choose the websockets connector
-    // name: 'webrtc'
-    // name: 'xmpp'
-    room: 'Textarea-example-dev'
-  },
-  sourceDir: '/bower_components', // location of the y-* modules
-  share: {
-    textarea: 'Text' // y.share.textarea is of type Y.Text
-  }
-  // types: ['Richtext', 'Array'] // optional list of types you want to import
-}).then(function (y) {
-  // bind the textarea to a shared text element
-  y.share.textarea.bind(document.getElementById('textfield'))
-}
+bower i yjs y-memory y-webrtc y-array y-text
 ```
 
-# Api
+Here is a simple example of a shared textarea
+```HTML
+  <!DOCTYPE html>
+  <html>
+    <body>
+      <script src="./bower_components/yjs/y.js"></script>
+      <!-- Yjs automatically includes all missing dependencies (browser only) -->
+      <script>
+        Y({
+          db: {
+            name: 'memory' // use memory database adapter.
+            // name: 'indexeddb' // use indexeddb database adapter instead for offline apps
+          },
+          connector: {
+            name: 'webrtc', // use webrtc connector
+            // name: 'websockets-client'
+            // name: 'xmpp'
+            room: 'my-room' // clients connecting to the same room share data
+          },
+          sourceDir: '/bower_components', // location of the y-* modules (browser only)
+          share: {
+            textarea: 'Text' // y.share.textarea is of type y-text
+          }
+        }).then(function (y) {
+          // The Yjs instance `y` is available
+          // y.share.* contains the shared types
+
+          // Bind `y.share.textarea` to `<textarea/>`
+          y.share.textarea.bind(document.querySelector('textarea'))
+        })
+      </script>
+      <textarea></textarea>
+    </body>
+  </html>
+```
+
+## Get Help & Give Help
+There are some friendly people on [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/y-js/yjs?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge) who are eager to help, and answer questions. Please join!
+
+Report _any_ issues to the
+[Github issue page](https://github.com/y-js/yjs/issues)! I try to fix them very
+soon, if possible.
+
+# API
 
 ### Y(options)
+* Y.extend(module1, module2, ..)
+  * Add extensions to Y
+  * `Y.extend(require('y-webrtc'))` has the same semantics as
+    `require('y-webrtc')(Y)`
 * options.db
-  * Will be forwarded to the database adapter. Specify the database adaper on `options.db.name`.
-  * Have a look at the used database adapter repository to see all available options.
+  * Will be forwarded to the database adapter. Specify the database adaper on
+    `options.db.name`.
+  * Have a look at the used database adapter repository to see all available
+    options.
 * options.connector
-  * Will be forwarded to the connector adapter. Specify the connector adaper on `options.connector.name`.
-  * All our connectors implement a `room` property. Clients that specify the same room share the same data.
-  * All of our connectors specify an `url` property that defines the connection endpoint of the used connector.
-    * All of our connectors also have a default connection endpoint that you can use for development. 
+  * Will be forwarded to the connector adapter. Specify the connector adaper on
+    `options.connector.name`.
+  * All our connectors implement a `room` property. Clients that specify the
+    same room share the same data.
+  * All of our connectors specify an `url` property that defines the connection
+    endpoint of the used connector.
+    * All of our connectors also have a default connection endpoint that you can
+      use for development.
+  * Set `options.connector.generateUserId = true` in order to genenerate a
+    userid, instead of receiving one from the server. This way the `Y(..)` is
+    immediately going to be resolved, without waiting for any confirmation from
+    the server. Use with caution.
   * Have a look at the used connector repository to see all available options.
-* options.sourceDir
-  * Path where all y-* modules are stored.
+  * *Only if you know what you are doing:* Set
+    `options.connector.preferUntransformed = true` in order receive the shared
+    data untransformed. This is very efficient as the database content is simply
+    copied to this client. This does only work if this client receives content
+    from only one client.
+* options.sourceDir (browser only)
+  * Path where all y-* modules are stored
   * Defaults to `/bower_components`
   * Not required when running on `nodejs` / `iojs`
-  * When using browserify you can specify all used modules like this:
+  * When using nodejs you need to manually extend Yjs:
 ```
 var Y = require('yjs')
-// you need to require the db, connector, and *all* types you use! 
+// you have to require a db, connector, and *all* types you use!
 require('y-memory')(Y)
 require('y-webrtc')(Y)
 require('y-map')(Y)
 // ..
-``` 
+```
 * options.share
-  * Specify on `options.share[arbitraryName]` types that are shared among all users.
-  * E.g. Specify `options.share[arbitraryName] = 'Array'` to require y-array and create an Y.Array type on `y.share[arbitraryName]`.
-  * If userA doesn't specify `options.share[arbitraryName]`, it won't be available for userA.
-  * If userB specifies `options.share[arbitraryName]`, it still won't be available for userA. But all the updates are send from userB to userA.
-  * In contrast to Y.Map, types on `y.share.*` cannot be overwritten or deleted. Instead, they are merged among all users. This feature is only available on `y.share.*`
-  * Weird behavior: It is supported that two users specify different types with the same property name.
-     E.g. userA specifies `options.share.x = 'Array'`, and userB specifies `options.share.x = 'Text'`. But they'll only share data if they specified the same type with the same property name
-* options.type
-  * Array of modules that Yjs needs to require, before instantiating a shared type.
-  * By default Yjs requires the specified database adapter, the specified connector, and all modules that are used in `options.share.*`
+  * Specify on `options.share[arbitraryName]` types that are shared among all
+    users.
+  * E.g. Specify `options.share[arbitraryName] = 'Array'` to require y-array and
+    create an y-array type on `y.share[arbitraryName]`.
+  * If userA doesn't specify `options.share[arbitraryName]`, it won't be
+    available for userA.
+  * If userB specifies `options.share[arbitraryName]`, it still won't be
+    available for userA. But all the updates are send from userB to userA.
+  * In contrast to y-map, types on `y.share.*` cannot be overwritten or deleted.
+    Instead, they are merged among all users. This feature is only available on
+    `y.share.*`
+  * Weird behavior: It is supported that two users specify different types with
+    the same property name.
+     E.g. userA specifies `options.share.x = 'Array'`, and userB specifies
+     `options.share.x = 'Text'`. But they only share data if they specified the
+     same type with the same property name
+* options.type (browser only)
+  * Array of modules that Yjs needs to require, before instantiating a shared
+    type.
+  * By default Yjs requires the specified database adapter, the specified
+    connector, and all modules that are used in `options.share.*`
   * Put all types here that you intend to use, but are not used in y.share.*
 
 ### Instantiated Y object (y)
@@ -137,7 +220,8 @@ require('y-map')(Y)
   * The specified database adapter is loaded
   * The specified connector is loaded
   * All types are included
-* The connector is initialized, and a unique user id is set (received from the server)
+* The connector is initialized, and a unique user id is set (received from the
+  server)
   * Note: When using y-indexeddb, a retrieved user id is stored on `localStorage`
 
 The promise returns an instance of Y. We denote it with a lower case `y`.
@@ -155,70 +239,57 @@ The promise returns an instance of Y. We denote it with a lower case `y`.
 * y.connector.disconnect()
   * Force to disconnect this instance from the other instances
 * y.connector.reconnect()
-  * Try to reconnect to the other instances (needs to be supported by the connector)
-  * Not supported by y-xmpp 
-* y.destroy()
+  * Try to reconnect to the other instances (needs to be supported by the
+    connector)
+  * Not supported by y-xmpp
+* y.close()
   * Destroy this object.
   * Destroys all types (they will throw weird errors if you still use them)
   * Disconnects from the other instances (via connector)
+  * Returns a promise
+* y.destroy()
+  * calls y.close()
   * Removes all data from the database
+  * Returns a promise
 * y.db.stopGarbageCollector()
-  * Stop the garbage collector. Call y.db.garbageCollect() to continue garbage collection
+  * Stop the garbage collector. Call y.db.garbageCollect() to continue garbage
+    collection
+* y.db.gc :: Boolean
+  * Whether gc is turned on
 * y.db.gcTimeout :: Number (defaults to 50000 ms)
   * Time interval between two garbage collect cycles
-  * It is required that all instances exchanged all messages after two garbage collect cycles (after 100000 ms per default)
+  * It is required that all instances exchanged all messages after two garbage
+    collect cycles (after 100000 ms per default)
 * y.db.userId :: String
   * The used user id for this client. **Never overwrite this**
 
-## Get help
-There are some friendly people on [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/y-js/yjs?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge) who may help you with your problem, and answer your questions.
+### Logging
+Yjs uses [debug](https://github.com/visionmedia/debug) for logging. The flag
+`y*` enables logging for all y-* components. You can selectively remove
+components you are not interested in: E.g. The flag `y*,-y:connector-message`
+will not log the long `y:connector-message` messages.
 
-Please report _any_ issues to the [Github issue page](https://github.com/y-js/yjs/issues)! I try to fix them very soon, if possible.
-If you want to see an issue fixed, please subscribe to the thread (or remind me via gitter).
+##### Enable logging in Node.js
+```sh
+DEBUG=y* node app.js
+```
 
+Remove the colors in order to log to a file:
+```sh
+DEBUG_COLORS=0 DEBUG=y* node app.js > log
+```
 
-## Changelog
-
-### 11.0.0
-
-* **All types now return a single event instead of list of events**
-  * Insert events contain a list of values
-* Improved performance for large insertions & deletions
-* Several bugfixes (offline editing related)
-* Native support for node 4 (see #49)
-
-### 10.0.0
-
-* Support for more complex types (a type can be a composition of several types)
-* Fixes several memory leaks
-
-### 9.0.0
-There were several rolling updates from 0.6 to 0.8. We consider Yjs stable since a long time, 
-and intend to continue stable releases. From this release forward y-* modules will implement peer-dependencies for npm, and dependencies for bower.
-Furthermore, incompatible yjs instances will now throw errors when syncing - this feature was influenced by #48. The versioning jump was influenced by react (see [here](https://facebook.github.io/react/blog/2016/02/19/new-versioning-scheme.html))
-
-
-### 0.6.0
-This is a complete rewrite of the 0.5 version of Yjs. Since Yjs 0.6.0 it is possible to work asynchronously on a persistent database, which enables offline support.
-* Switched to semver versioning
-* Requires a promise implementation in environment (es6 promises suffice, included in all the major browsers). Otherwise you have to include a polyfill
-* Y.Object has been renamed to Y.Map
-* Y.Map exchanges `.val(name [, value])` in favor of `.set(name, value)` and `.get(name)`
-* Y.Map `.get(name)` returns a promise, if the value is a custom type
-* The Connector definition slightly changed (I'll update the wiki)
-* The Type definitions completely changed, so you have to rewrite them (I'll rewrite the article in the wiki)
-* Support for several packaging systems
-* Flowtype
-
+##### Enable logging in the browser
+```js
+localStorage.debug = 'y*'
+```
 
 ## Contribution
-I created this framework during my bachelor thesis at the chair of computer science 5 [(i5)](http://dbis.rwth-aachen.de/cms), RWTH University. Since December 2014 I'm working on Yjs as a part of my student worker job at the i5.
+I created this framework during my bachelor thesis at the chair of computer
+science 5 [(i5)](http://dbis.rwth-aachen.de/cms), RWTH University. Since
+December 2014 I'm working on Yjs as a part of my student worker job at the i5.
 
 ## License
-Yjs is licensed under the [MIT License](./LICENSE.txt).
+Yjs is licensed under the [MIT License](./LICENSE).
 
 <yjs@dbis.rwth-aachen.de>
-
-[ShareJs]: https://github.com/share/ShareJS
-[OpenCoweb]: https://github.com/opencoweb/coweb/wiki
-

declarations/Structs.js

@@ -1,72 +0,0 @@
-/* @flow */
-
-type UserId = string
-type Id = [UserId, number|string]
-
-/*
-type Struct = {
-  id: Id,
-  left?: Id,
-  right?: Id,
-  target?: Id,
-  struct: 'Insert' | 'Delete'
-}*/
-
-type Struct = Insertion | Deletion
-type Operation = Struct
-
-type Insertion = {
-  id: Id,
-  left: ?Id,
-  origin: ?Id,
-  right: ?Id,
-  parent: Id,
-  parentSub: ?Id,
-  opContent: ?Id,
-  content: ?any,
-  struct: 'Insert'
-}
-
-type Deletion = {
-  target: Id,
-  struct: 'Delete'
-}
-
-type MapStruct = {
-  id: Id,
-  type: TypeNames,
-  map: any
-}
-
-type ListStruct = {
-  id: Id,
-  type: TypeNames,
-  start: Id,
-  end: Id
-}
-
-
-type MessageSyncStep1 = {
-  type: 'sync step 1',
-  deleteSet: any,
-  stateSet: any
-}
-
-type MessageSyncStep2 = {
-  type: 'sync step 2',
-  os: Array<Operation>,
-  deleteSet: any,
-  stateSet: any
-}
-
-type MessageUpdate = {
-  type: 'update',
-  ops: Array<Operation>
-}
-
-type MessageSyncDone = {
-  type: 'sync done'
-}
-
-type Message = MessageSyncStep1 | MessageSyncStep2 | MessageUpdate | MessageSyncDone
-

declarations/Y.js

@@ -1,34 +0,0 @@
-/* @flow */
-
-type YGlobal = {
-	utils: Object,
-	Struct: any,
-	AbstractDatabase: any,
-	AbstractConnector: any,
-	Transaction: any
-}
-
-type YConfig = {
-	db: Object,
-	connector: Object,
-	root: Object
-}
-
-type TypeName = 'array' | 'map' | 'text'
-
-declare var YConcurrency_TestingMode : boolean
-
-type Transaction<A> = Generator<any, A, any>
-
-type SyncRole = 'master' | 'slave'
-
-declare class Store {
-	find: (id:Id) => Transaction<any>;
-	put: (n:any) => Transaction<void>;
-	delete: (id:Id) => Transaction<void>;
-	findWithLowerBound: (start:Id) => Transaction<any>;
-	findWithUpperBound: (end:Id) => Transaction<any>;
-	findNext: (id:Id) => Transaction<any>;
-	findPrev: (id:Id) => Transaction<any>;
-	iterate: (t:any,start:?Id,end:?Id,gen:any) => Transaction<any>;
-}

examples/ace/index.html

@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <style type="text/css" media="screen">
+    #aceContainer {
+        position: absolute;
+        top: 0;
+        right: 0;
+        bottom: 0;
+        left: 0;
+    }
+    .inserted {
+      position:absolute;
+      z-index:20;
+      background-color: #FFC107;
+    }
+    .deleted {
+      position:absolute;
+      z-index:20;
+      background-color: #FFC107;
+    }
+    </style>
+  </head>
+  <body>
+
+    <div id="aceContainer"></div>
+    <script src="../bower_components/yjs/y.js"></script>
+    <script src="../bower_components/ace-builds/src/ace.js"></script>
+
+    <script src="./index.js"></script>
+  </body>
+</html>

examples/ace/index.js

@@ -0,0 +1,24 @@
+/* global Y, ace */
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'ace-example'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    ace: 'Text' // y.share.textarea is of type Y.Text
+  }
+}).then(function (y) {
+  window.yAce = y
+
+  // bind the textarea to a shared text element
+  var editor = ace.edit('aceContainer')
+  editor.setTheme('ace/theme/chrome')
+  editor.getSession().setMode('ace/mode/javascript')
+
+  y.share.ace.bindAce(editor)
+})

examples/bower.json

@@ -0,0 +1,19 @@
+{
+  "name": "yjs-examples",
+  "version": "0.0.0",
+  "homepage": "y-js.org",
+  "authors": [
+    "Kevin Jahns <kevin.jahns@rwth-aachen.de>"
+  ],
+  "description": "Examples for Yjs",
+  "license": "MIT",
+  "ignore": [],
+  "dependencies": {
+    "quill": "^1.0.0-rc.2",
+    "ace": "~1.2.3",
+    "ace-builds": "~1.2.3",
+    "jquery": "~2.2.2",
+    "d3": "^3.5.16",
+    "codemirror": "^5.25.0"
+  }
+}

examples/chat/index.html

@@ -0,0 +1,19 @@
+<!DOCTYPE html>
+<html>
+  <body>
+    <style>
+      #chat p span {
+        color: blue;
+      }
+    </style>
+    <div id="chat"></div>
+    <form id="chatform">
+      <input name="username" type="text" style="width:15%;">
+      <input name="message" type="text" style="width:60%;">
+      <input type="submit" value="Send">
+    </form>
+    <script src="../../y.js"></script>
+    <script src="../../../y-websockets-client/dist/y-websockets-client.js"></script>
+    <script src="./index.js"></script>
+  </body>
+</html>

examples/chat/index.js

@@ -0,0 +1,71 @@
+/* global Y */
+
+// initialize a shared object. This function call returns a promise!
+var y = new Y({
+  connector: {
+    name: 'websockets-client',
+    room: 'chat-example'
+  }
+})
+
+window.yChat = y
+
+let chatprotocol = y.define('chatprotocol', Y.Array)
+
+let chatcontainer = document.querySelector('#chat')
+
+// This functions inserts a message at the specified position in the DOM
+function appendMessage (message, position) {
+  var p = document.createElement('p')
+  var uname = document.createElement('span')
+  uname.appendChild(document.createTextNode(message.username + ': '))
+  p.appendChild(uname)
+  p.appendChild(document.createTextNode(message.message))
+  chatcontainer.insertBefore(p, chatcontainer.children[position] || null)
+}
+// This function makes sure that only 7 messages exist in the chat history.
+// The rest is deleted
+function cleanupChat () {
+  if (chatprotocol.length > 7) {
+    chatprotocol.delete(0, chatprotocol.length - 7)
+  }
+}
+// Insert the initial content
+chatprotocol.toArray().forEach(appendMessage)
+cleanupChat()
+
+// whenever content changes, make sure to reflect the changes in the DOM
+chatprotocol.observe(function (event) {
+  if (event.type === 'insert') {
+    for (let i = 0; i < event.length; i++) {
+      appendMessage(event.values[i], event.index + i)
+    }
+  } else if (event.type === 'delete') {
+    for (let i = 0; i < event.length; i++) {
+      chatcontainer.children[event.index].remove()
+    }
+  }
+  // concurrent insertions may result in a history > 7, so cleanup here
+  cleanupChat()
+})
+document.querySelector('#chatform').onsubmit = function (event) {
+  // the form is submitted
+  var message = {
+    username: this.querySelector('[name=username]').value,
+    message: this.querySelector('[name=message]').value
+  }
+  if (message.username.length > 0 && message.message.length > 0) {
+    if (chatprotocol.length > 6) {
+      // If we are goint to insert the 8th element, make sure to delete first.
+      chatprotocol.delete(0)
+    }
+    // Here we insert a message in the shared chat type.
+    // This will call the observe function (see line 40)
+    // and reflect the change in the DOM
+    chatprotocol.push([message])
+    this.querySelector('[name=message]').value = ''
+  }
+  // Do not send this form!
+  event.preventDefault()
+  return false
+}

examples/codemirror/index.html

@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html>
+  <head>
+  </head>
+  <body>
+    <div id="codeMirrorContainer"></div>
+
+    <script src="../bower_components/yjs/y.js"></script>
+    <script src="../bower_components/codemirror/lib/codemirror.js"></script>
+    <script src="../bower_components/codemirror/mode/javascript/javascript.js"></script>
+    <link rel="stylesheet" href="../bower_components/codemirror/lib/codemirror.css">
+    <style>
+      .CodeMirror {
+        position: fixed;
+        top: 0;
+        left: 0;
+        height: 100%;
+        width: 100%;
+      }
+    </style>
+    <script src="./index.js"></script>
+  </body>
+</html>

examples/codemirror/index.js

@@ -0,0 +1,24 @@
+/* global Y, CodeMirror */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'codemirror-example'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    codemirror: 'Text' // y.share.codemirror is of type Y.Text
+  }
+}).then(function (y) {
+  window.yCodeMirror = y
+
+  var editor = CodeMirror(document.querySelector('#codeMirrorContainer'), {
+    mode: 'javascript',
+    lineNumbers: true
+  })
+  y.share.codemirror.bindCodeMirror(editor)
+})

examples/drawing/index.html

@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html>
+<body>
+  <style>
+    path {
+      fill: none;
+      stroke: blue;
+      stroke-width: 1px;
+      stroke-linejoin: round;
+      stroke-linecap: round;
+    }
+  </style>
+  <button type="button" id="clearDrawingCanvas">Clear Drawing</button>
+  <svg id="drawingCanvas" viewbox="0 0 100 100" width="100%"></svg>
+  <script src="../../y.js"></script>
+  <script src="../../../y-array/y-array.js"></script>
+  <script src="../../../y-map/dist/y-map.js"></script>
+  <script src="../../../y-memory/y-memory.js"></script>
+  <script src="../../../y-websockets-client/y-websockets-client.js"></script>
+  <script src="../bower_components/d3/d3.js"></script>
+  <script src="./index.js"></script>
+</body>
+</html>

examples/drawing/index.js

@@ -0,0 +1,84 @@
+/* globals Y, d3 */
+'strict mode'
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'drawing-example',
+    url: 'localhost:1234'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    drawing: 'Array'
+  }
+}).then(function (y) {
+  window.yDrawing = y
+  var drawing = y.share.drawing
+  var renderPath = d3.svg.line()
+    .x(function (d) { return d[0] })
+    .y(function (d) { return d[1] })
+    .interpolate('basis')
+
+  var svg = d3.select('#drawingCanvas')
+    .call(d3.behavior.drag()
+      .on('dragstart', dragstart)
+      .on('drag', drag)
+      .on('dragend', dragend))
+
+  // create line from a shared array object and update the line when the array changes
+  function drawLine (yarray) {
+    var line = svg.append('path').datum(yarray.toArray())
+    line.attr('d', renderPath)
+    yarray.observe(function (event) {
+      // we only implement insert events that are appended to the end of the array
+      event.values.forEach(function (value) {
+        line.datum().push(value)
+      })
+      line.attr('d', renderPath)
+    })
+  }
+  // call drawLine every time an array is appended
+  y.share.drawing.observe(function (event) {
+    if (event.type === 'insert') {
+      event.values.forEach(drawLine)
+    } else {
+      // just remove all elements (thats what we do anyway)
+      svg.selectAll('path').remove()
+    }
+  })
+  // draw all existing content
+  for (var i = 0; i < drawing.length; i++) {
+    drawLine(drawing.get(i))
+  }
+
+  // clear canvas on request
+  document.querySelector('#clearDrawingCanvas').onclick = function () {
+    drawing.delete(0, drawing.length)
+  }
+
+  var sharedLine = null
+  function dragstart () {
+    drawing.insert(drawing.length, [Y.Array])
+    sharedLine = drawing.get(drawing.length - 1)
+  }
+
+  // After one dragged event is recognized, we ignore them for 33ms.
+  var ignoreDrag = null
+  function drag () {
+    if (sharedLine != null && ignoreDrag == null) {
+      ignoreDrag = window.setTimeout(function () {
+        ignoreDrag = null
+      }, 33)
+      sharedLine.push([d3.mouse(this)])
+    }
+  }
+
+  function dragend () {
+    sharedLine = null
+    window.clearTimeout(ignoreDrag)
+    ignoreDrag = null
+  }
+})

examples/html-editor/index.html

@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html>
+</head>
+  <!-- jquery is not required for y-xml. It is just here for convenience, and to test batch operations. -->
+  <script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
+  <script src="../yjs-dist.js"></script>
+  <script src="./index.js"></script>
+</head>
+<body contenteditable="true">
+</body>
+</html>

examples/html-editor/index.js

@@ -0,0 +1,43 @@
+/* global Y, HTMLElement, customElements */
+
+class MagicTable extends HTMLElement {
+  constructor () {
+    super()
+    var shadow = this.attachShadow({mode: 'open'})
+    setTimeout(() => {
+      shadow.append(this.childNodes[0])
+    }, 1000)
+  }
+}
+customElements.define('magic-table', MagicTable)
+
+// initialize a shared object. This function call returns a promise!
+let y = new Y({
+  connector: {
+    name: 'websockets-client',
+    url: 'http://127.0.0.1:1234',
+    room: 'html-editor-example6'
+    // maxBufferLength: 100
+  }
+})
+window.yXml = y
+window.yXmlType = y.define('xml', Y.XmlFragment)
+window.onload = function () {
+  console.log('start!')
+  // Bind children of XmlFragment to the document.body
+  window.yXmlType.bindToDom(document.body)
+}
+window.undoManager = new Y.utils.UndoManager(window.yXmlType, {
+  captureTimeout: 500
+})
+
+document.onkeydown = function interceptUndoRedo (e) {
+  if (e.keyCode === 90 && e.metaKey) {
+    if (!e.shiftKey) {
+      window.undoManager.undo()
+    } else {
+      window.undoManager.redo()
+    }
+    e.preventDefault()
+  }
+}

examples/indexeddb/index.html

@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<html>
+  <head>
+  </head>
+  <body>
+    <div id="codeMirrorContainer"></div>
+    <script src="../bower_components/codemirror/lib/codemirror.js"></script>
+    <script src="../bower_components/codemirror/mode/javascript/javascript.js"></script>
+    <link rel="stylesheet" href="../bower_components/codemirror/lib/codemirror.css">
+    <style>
+      .CodeMirror {
+        position: fixed;
+        top: 0;
+        left: 0;
+        height: 100%;
+        width: 100%;
+      }
+    </style>
+    <script type="module" src="./index.js"></script>
+  </body>
+</html>

examples/indexeddb/index.js

@@ -0,0 +1,24 @@
+/* global Y, CodeMirror */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'codemirror-example'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    codemirror: 'Text' // y.share.codemirror is of type Y.Text
+  }
+}).then(function (y) {
+  window.yCodeMirror = y
+
+  var editor = CodeMirror(document.querySelector('#codeMirrorContainer'), {
+    mode: 'javascript',
+    lineNumbers: true
+  })
+  y.share.codemirror.bindCodeMirror(editor)
+})

examples/infiniteyjs/index.html

@@ -0,0 +1,58 @@
+<!DOCTYPE html>
+<html>
+<body>
+  <style>
+    .wrapper {
+      display: grid;
+      grid-template-columns: repeat(3, 1fr);
+      grid-gap: 7px;
+    }
+    .one {
+      grid-column: 1 ;
+    }
+    .two { 
+      grid-column: 2;
+    }
+    .three {
+      grid-column: 3;
+    }
+    textarea {
+      width: calc(100% - 10px)
+    }
+    .editor-container {
+      background-color: #4caf50;
+      padding: 4px 5px 10px 5px;
+      border-radius: 11px;
+    }
+    .editor-container[disconnected] {
+      background-color: red;
+    }
+    .disconnected-info {
+      display: none;
+    }
+    .editor-container[disconnected] .disconnected-info {
+      display: inline;
+    }
+  </style>
+  <div class="wrapper">
+    <div id="container1" class="one editor-container">
+      <h1>Server 1 <span class="disconnected-info">(disconnected)</span></h1>
+      <textarea id="textarea1" rows=40 autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
+    </div>
+    <div id="container2" class="two editor-container">
+      <h1>Server 2 <span class="disconnected-info">(disconnected)</span></h1>
+      <textarea id="textarea2" rows=40 autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
+    </div>
+    <div id="container3" class="three editor-container">
+      <h1>Server 3 <span class="disconnected-info">(disconnected)</span></h1>
+      <textarea id="textarea3" rows=40 autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
+    </div>
+  </div>
+  <script src="../../y.js"></script>
+  <script src="../../../y-array/y-array.js"></script>
+  <script src="../../../y-text/dist/y-text.js"></script>
+  <script src="../../../y-memory/y-memory.js"></script>
+  <script src="../../../y-websockets-client/y-websockets-client.js"></script>
+  <script src="./index.js"></script>
+</body>
+</html>

examples/infiniteyjs/index.js

@@ -0,0 +1,64 @@
+/* global Y */
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Textarea-example',
+    url: 'https://yjs-v13.herokuapp.com/'
+  },
+  share: {
+    textarea: 'Text'
+  }
+}).then(function (y) {
+  window.y1 = y
+  y.share.textarea.bind(document.getElementById('textarea1'))
+})
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Textarea-example',
+    url: 'https://yjs-v13-second.herokuapp.com/'
+  },
+  share: {
+    textarea: 'Text'
+  }
+}).then(function (y) {
+  window.y2 = y
+  y.share.textarea.bind(document.getElementById('textarea2'))
+  y.connector.socket.on('connection', function () {
+    document.getElementById('container2').removeAttribute('disconnected')
+  })
+  y.connector.socket.on('disconnect', function () {
+    document.getElementById('container2').setAttribute('disconnected', true)
+  })
+})
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Textarea-example',
+    url: 'https://yjs-v13-third.herokuapp.com/'
+  },
+  share: {
+    textarea: 'Text'
+  }
+}).then(function (y) {
+  window.y3 = y
+  y.share.textarea.bind(document.getElementById('textarea3'))
+  y.connector.socket.on('connection', function () {
+    document.getElementById('container3').removeAttribute('disconnected')
+  })
+  y.connector.socket.on('disconnect', function () {
+    document.getElementById('container3').setAttribute('disconnected', true)
+  })
+})

examples/jigsaw/index.html

@@ -0,0 +1,26 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <style type="text/css">
+    .draggable {
+      cursor: move;
+    }
+  </style>
+</head>
+<body>
+  <svg id="puzzle-example" width="100%" viewBox="0 0 800 800">
+    <g>
+      <path d="M 311.76636,154.23389 C 312.14136,171.85693 318.14087,184.97998 336.13843,184.23047 C 354.13647,183.48047 351.88647,180.48096 354.88599,178.98096 C 357.8855,177.48096 368.38452,170.35693 380.00806,169.98193 C 424.61841,168.54297 419.78296,223.6001 382.25757,223.6001 C 377.75806,223.6001 363.51001,219.10107 356.38599,211.97656 C 349.26196,204.85254 310.64185,207.10254 314.76636,236.34863 C 316.34888,247.5708 324.08374,267.90723 324.84595,286.23486 C 325.29321,296.99414 323.17603,307.00635 321.58911,315.6377 C 360.11353,305.4585 367.73462,304.30518 404.00513,312.83936 C 410.37915,314.33887 436.62573,310.21436 421.25269,290.3418 C 405.87964,270.46924 406.25464,248.34717 417.12817,240.84814 C 428.00171,233.34912 446.74976,228.84961 457.99829,234.09912 C 469.24683,239.34814 484.61987,255.84619 475.24585,271.59424 C 465.87231,287.34229 452.74878,290.7168 456.49829,303.84033 C 460.2478,316.96387 479.74536,320.33838 500.74292,321.83789 C 509.70142,322.47803 527.97192,323.28467 542.10864,320.12939 C 549.91821,318.38672 556.92212,315.89502 562.46753,313.56396 C 561.40796,277.80664 560.84888,245.71729 560.3606,241.97314 C 558.85278,230.41455 542.49536,217.28564 525.86499,223.2251 C 520.61548,225.1001 519.86548,231.84912 505.24243,232.59912 C 444.92798,235.69238 462.06958,143.26709 525.86499,180.48096 C 539.52759,188.45068 575.19409,190.7583 570.10913,156.85889 C 567.85962,141.86035 553.98608,102.86523 553.98608,102.86523 C 553.98608,102.86523 477.23755,111.82227 451.99878,91.991699 C 441.50024,83.74292 444.87476,69.494629 449.37427,61.245605 C 453.87378,52.996582 465.12231,46.622559 464.74731,36.123779 C 463.02563,-12.086426 392.96704,-10.902832 396.5061,36.873535 C 397.25562,46.997314 406.62964,52.621582 410.75415,60.495605 C 420.00757,78.161377 405.50024,96.073486 384.50757,99.490723 C 377.36206,100.65381 349.17505,102.65332 320.39429,102.23486 C 319.677,102.22461 318.95923,102.21143 318.24194,102.19775 C 315.08423,120.9751 311.55688,144.39697 311.76636,154.23389 z " style="fill:#f2c569;stroke:#000000" id="path2502"/>
+      <path d="M 500.74292,321.83789 C 479.74536,320.33838 460.2478,316.96387 456.49829,303.84033 C 452.74878,290.7168 465.87231,287.34229 475.24585,271.59424 C 484.61987,255.84619 469.24683,239.34814 457.99829,234.09912 C 446.74976,228.84961 428.00171,233.34912 417.12817,240.84814 C 406.25464,248.34717 405.87964,270.46924 421.25269,290.3418 C 436.62573,310.21436 410.37915,314.33887 404.00513,312.83936 C 367.73462,304.30518 360.11353,305.4585 321.58911,315.6377 C 320.56372,321.21484 319.75854,326.2207 320.01538,330.46191 C 320.76538,342.83545 329.3894,385.95508 327.8894,392.7041 C 326.3894,399.45312 313.64136,418.20117 297.89331,407.32715 C 282.14526,396.45361 276.52075,393.4541 265.27222,394.5791 C 254.02368,395.70361 239.77563,402.07812 239.77563,419.32568 C 239.77563,436.57373 250.27417,449.69727 268.64673,447.82227 C 287.36353,445.9126 317.92163,423.11035 325.63989,452.69678 C 330.1394,469.94434 330.51392,487.19238 330.1394,498.44092 C 329.95825,503.87646 326.09985,518.06592 322.16089,531.28125 C 353.2854,532.73682 386.47095,531.26611 394.2561,529.93701 C 430.30933,523.78174 429.31909,496.09766 412.62866,477.44385 C 406.25464,470.31934 401.75513,455.32129 405.87964,444.82275 C 414.07056,423.97314 458.8064,422.17773 473.37134,438.82324 C 483.86987,450.82178 475.99585,477.44385 468.49683,482.69287 C 453.52222,493.17529 457.22485,516.83008 473.37134,528.06201 C 504.79126,549.91943 572.35913,535.56152 572.35913,535.56152 C 572.35913,535.56152 567.85962,498.06592 567.48462,471.81934 C 567.10962,445.57275 589.60669,450.07227 593.3562,450.07227 C 597.10571,450.07227 604.22974,455.32129 609.47925,459.4458 C 614.72876,463.57031 618.85327,469.94434 630.85181,470.69434 C 677.43726,473.60596 674.58813,420.7373 631.97632,413.32666 C 623.35229,411.82666 614.72876,416.32617 603.10522,424.57519 C 591.48169,432.82422 577.23315,425.32519 570.10913,417.45117 C 566.07788,412.99561 563.8479,360.16406 562.46753,313.56396 C 556.92212,315.89502 549.91821,318.38672 542.10864,320.12939 C 527.97192,323.28467 509.70142,322.47803 500.74292,321.83789 z " style="fill:#f3f3d6;stroke:#000000" id="path2504"/>
+      <path d="M 240.52563,141.86035 C 257.60327,159.6499 243.94507,188.68799 214.65356,190.22949 C 185.09448,191.78516 164.66675,157.17822 190.28589,136.61621 C 200.49585,128.42139 198.05786,114.12158 179.78296,106.98975 C 154.4187,97.091553 90.54419,107.73975 90.54419,107.73975 C 90.54419,107.73975 100.88794,135.11328 101.41772,168.48242 C 101.79272,192.104 68.796875,189.47949 63.172607,186.85498 C 57.54834,184.23047 45.924805,173.73145 37.675781,173.73145 C -14.411865,173.73145 -10.013184,245.84375 39.925537,232.22412 C 48.174316,229.97461 56.42334,220.97559 68.796875,222.47559 C 81.17041,223.9751 87.544434,232.59912 87.544434,246.09766 C 87.544434,252.51709 87.0354,281.24268 86.340576,312.87012 C 119.15894,313.67676 160.60962,314.46582 170.03442,313.58887 C 186.15698,312.08936 195.90601,301.59033 188.40698,293.3418 C 180.90796,285.09277 156.16089,256.59619 179.03296,239.34814 C 201.90503,222.10059 235.65112,231.84912 239.77563,247.22217 C 243.90015,262.59521 240.52563,273.46924 234.90112,279.09326 C 229.27661,284.71777 210.52905,298.96582 221.40259,308.71484 C 232.27661,318.46338 263.77222,330.83691 302.39282,320.71338 C 309.58862,318.82715 315.92114,317.13525 321.58911,315.6377 C 323.17603,307.00635 325.29321,296.99414 324.84595,286.23486 C 324.08374,267.90723 316.34888,247.5708 314.76636,236.34863 C 310.64185,207.10254 349.26196,204.85254 356.38599,211.97656 C 363.51001,219.10107 377.75806,223.6001 382.25757,223.6001 C 419.78296,223.6001 424.61841,168.54297 380.00806,169.98193 C 368.38452,170.35693 357.8855,177.48096 354.88599,178.98096 C 351.88647,180.48096 354.13647,183.48047 336.13843,184.23047 C 318.14087,184.97998 312.14136,171.85693 311.76636,154.23389 C 311.55688,144.39697 315.08423,120.9751 318.24194,102.19775 C 290.37524,101.67725 262.46069,98.968262 254.39868,97.991211 C 233.38013,95.443359 217.17456,117.53662 240.52563,141.86035 z " style="fill:#bebcdb;stroke:#000000" id="path2506"/>
+      <path d="M 325.63989,452.69678 C 317.92163,423.11035 287.36353,445.9126 268.64673,447.82227 C 250.27417,449.69727 239.77563,436.57373 239.77563,419.32568 C 239.77563,402.07812 254.02368,395.70361 265.27222,394.5791 C 276.52075,393.4541 282.14526,396.45361 297.89331,407.32715 C 313.64136,418.20117 326.3894,399.45313 327.8894,392.7041 C 329.3894,385.95508 320.76538,342.83545 320.01538,330.46191 C 319.75855,326.2207 320.56372,321.21484 321.58911,315.6377 C 315.92114,317.13525 309.58862,318.82715 302.39282,320.71338 C 263.77222,330.83691 232.27661,318.46338 221.40259,308.71484 C 210.52905,298.96582 229.27661,284.71777 234.90112,279.09326 C 240.52563,273.46924 243.90015,262.59521 239.77563,247.22217 C 235.65112,231.84912 201.90503,222.10059 179.03296,239.34814 C 156.16089,256.59619 180.90796,285.09277 188.40698,293.3418 C 195.90601,301.59033 186.15698,312.08936 170.03442,313.58887 C 160.60962,314.46582 119.15894,313.67676 86.340576,312.87012 C 85.573975,347.74561 84.581299,386.15088 83.794922,402.07812 C 82.295166,432.44922 109.29175,422.32568 115.66577,420.82568 C 122.04028,419.32568 126.16479,409.57715 143.03735,408.45215 C 185.9231,405.59326 186.09985,466.69629 144.16235,467.69482 C 128.41431,468.06982 113.79126,451.19678 108.16675,447.44727 C 102.54272,443.69775 87.919433,442.94775 83.794922,457.9458 C 82.01709,464.41113 78.118652,481.65137 78.098144,496.18994 C 78.071045,515.38037 82.295166,531.81201 82.295166,531.81201 C 82.295166,531.81201 105.54224,526.5625 149.41187,526.5625 C 193.28149,526.5625 199.65552,547.93506 194.78101,558.80859 C 189.90649,569.68213 181.28296,568.93213 179.40796,583.18066 C 172.7063,634.11133 253.34106,631.08203 249.14917,584.68018 C 247.96948,571.62354 237.16528,571.66699 232.27661,557.68359 C 222.17944,528.80273 244.64966,523.56299 257.39819,524.68799 C 263.59351,525.23437 290.95679,529.73389 320.75757,531.21582 C 321.22437,531.23877 321.69312,531.25928 322.16089,531.28125 C 326.09985,518.06592 329.95825,503.87646 330.1394,498.44092 C 330.51392,487.19238 330.1394,469.94434 325.63989,452.69678 z " style="fill:#d3ea9d;stroke:#000000" id="path2508"/>
+		</g>
+  </svg>
+  <script src="../../y.js"></script>
+  <script src="../../../y-map/dist/y-map.js"></script>
+  <script src="../../../y-memory/y-memory.js"></script>
+  <script src="../../../y-websockets-client/y-websockets-client.js"></script>
+  <script src="../bower_components/d3/d3.js"></script>
+  <script src="./index.js"></script>
+</body>
+</html>

examples/jigsaw/index.js

@@ -0,0 +1,74 @@
+/* @flow */
+/* global Y, d3 */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Puzzle-example',
+    url: 'http://localhost:1234'
+  },
+  share: {
+    piece1: 'Map',
+    piece2: 'Map',
+    piece3: 'Map',
+    piece4: 'Map'
+  }
+}).then(function (y) {
+  window.yJigsaw = y
+  var origin // mouse start position - translation of piece
+  var drag = d3.behavior.drag()
+    .on('dragstart', function (params) {
+      // get the translation of the element
+      var translation = d3
+        .select(this)
+        .attr('transform')
+        .slice(10, -1)
+        .split(',')
+        .map(Number)
+      // mouse coordinates
+      var mouse = d3.mouse(this.parentNode)
+      origin = {
+        x: mouse[0] - translation[0],
+        y: mouse[1] - translation[1]
+      }
+    })
+    .on('drag', function () {
+      var mouse = d3.mouse(this.parentNode)
+      var x = mouse[0] - origin.x // =^= mouse - mouse at dragstart + translation at dragstart
+      var y = mouse[1] - origin.y
+      d3.select(this).attr('transform', 'translate(' + x + ',' + y + ')')
+    })
+    .on('dragend', function (piece, i) {
+      // save the current translation of the puzzle piece
+      var mouse = d3.mouse(this.parentNode)
+      var x = mouse[0] - origin.x
+      var y = mouse[1] - origin.y
+      piece.set('translation', {x: x, y: y})
+    })
+
+  var data = [y.share.piece1, y.share.piece2, y.share.piece3, y.share.piece4]
+  var pieces = d3.select(document.querySelector('#puzzle-example')).selectAll('path').data(data)
+
+  pieces
+    .classed('draggable', true)
+    .attr('transform', function (piece) {
+      var translation = piece.get('translation') || {x: 0, y: 0}
+      return 'translate(' + translation.x + ',' + translation.y + ')'
+    }).call(drag)
+
+  data.forEach(function (piece) {
+    piece.observe(function () {
+      // whenever a property of a piece changes, update the translation of the pieces
+      pieces
+        .transition()
+        .attr('transform', function (piece) {
+          var translation = piece.get('translation') || {x: 0, y: 0}
+          return 'translate(' + translation.x + ',' + translation.y + ')'
+        })
+    })
+  })
+})

examples/monaco/index.html

@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html>
+  <head>
+  </head>
+  <body>
+    <div id="monacoContainer"></div>
+    <style>
+      #monacoContainer {
+        position: fixed;
+        top: 0;
+        left: 0;
+        height: 100%;
+        width: 100%;
+      }
+    </style>
+    <script src="../bower_components/yjs/y.js"></script>
+    <script src="../bower_components/y-array/y-array.js"></script>
+    <script src="../bower_components/y-text/y-text.js"></script>
+    <script src="../bower_components/y-websockets-client/y-websockets-client.js"></script>
+    <script src="../bower_components/y-memory/y-memory.js"></script>
+    <script src="../node_modules/monaco-editor/min/vs/loader.js"></script>
+    <script src="./index.js"></script>
+  </body>
+</html>

examples/monaco/index.js

@@ -0,0 +1,30 @@
+/* global Y, monaco */
+
+require.config({ paths: { 'vs': '../node_modules/monaco-editor/min/vs' } })
+
+require(['vs/editor/editor.main'], function () {
+  // Initialize a shared object. This function call returns a promise!
+  Y({
+    db: {
+      name: 'memory'
+    },
+    connector: {
+      name: 'websockets-client',
+      room: 'monaco-example'
+    },
+    sourceDir: '/bower_components',
+    share: {
+      monaco: 'Text' // y.share.monaco is of type Y.Text
+    }
+  }).then(function (y) {
+    window.yMonaco = y
+
+    // Create Monaco editor
+    var editor = monaco.editor.create(document.getElementById('monacoContainer'), {
+      language: 'javascript'
+    })
+
+    // Bind to y.share.monaco
+    y.share.monaco.bindMonaco(editor)
+  })
+})

examples/package.json

@@ -0,0 +1,20 @@
+{
+  "name": "examples",
+  "version": "0.0.0",
+  "description": "",
+  "scripts": {
+    "dist": "rollup -c",
+    "watch": "rollup -cw"
+  },
+  "author": "Kevin Jahns",
+  "license": "MIT",
+  "dependencies": {
+    "monaco-editor": "^0.8.3"
+  },
+  "devDependencies": {
+    "standard": "^10.0.2"
+  },
+  "standard": {
+    "ignore": ["bower_components"]
+  }
+}

examples/quill/index.html

@@ -0,0 +1,35 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <!-- quill does not include dist files! We are using the hosted version instead -->
+  <!--link rel="stylesheet" href="../bower_components/quill/dist/quill.snow.css" /-->
+  <link href="https://cdn.quilljs.com/1.0.4/quill.snow.css" rel="stylesheet">
+  <link href="https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.5.1/katex.min.css" rel="stylesheet">
+  <link href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.2.0/styles/monokai-sublime.min.css" rel="stylesheet">
+  <style>
+    #quill-container {
+      border: 1px solid gray;
+      box-shadow: 0px 0px 10px gray;
+    }
+  </style>
+</head>
+<body>
+  <div id="quill-container">
+    <div id="quill">
+    </div>
+  </div>
+
+  <script src="https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.5.1/katex.min.js" type="text/javascript"></script>
+  <script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.2.0/highlight.min.js" type="text/javascript"></script>
+  <script src="https://cdn.quilljs.com/1.0.4/quill.js"></script>
+  <!-- quill does not include dist files! We are using the hosted version instead (see above)
+  <script src="../bower_components/quill/dist/quill.js"></script>
+  -->
+  <script src="../../y.js"></script>
+  <script src="../../../y-array/y-array.js"></script>
+  <script src="../../../y-richtext/dist/y-richtext.js"></script>
+  <script src="../../../y-memory/y-memory.js"></script>
+  <script src="../../../y-websockets-client/y-websockets-client.js"></script>
+  <script src="./index.js"></script>
+</body>
+</html>

examples/quill/index.js

@@ -0,0 +1,40 @@
+/* global Y, Quill */
+
+// initialize a shared object. This function call returns a promise!
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'richtext-example-quill-1.0-test',
+    url: 'http://localhost:1234'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    richtext: 'Richtext' // y.share.richtext is of type Y.Richtext
+  }
+}).then(function (y) {
+  window.yQuill = y
+
+  // create quill element
+  window.quill = new Quill('#quill', {
+    modules: {
+      formula: true,
+      syntax: true,
+      toolbar: [
+        [{ size: ['small', false, 'large', 'huge'] }],
+        ['bold', 'italic', 'underline'],
+        [{ color: [] }, { background: [] }],    // Snow theme fills in values
+        [{ script: 'sub' }, { script: 'super' }],
+        ['link', 'image'],
+        ['link', 'code-block'],
+        [{ list: 'ordered' }]
+      ]
+    },
+    theme: 'snow'
+  })
+  // bind quill to richtext type
+  y.share.richtext.bind(window.quill)
+})

examples/rollup.config.js

@@ -0,0 +1,27 @@
+import nodeResolve from 'rollup-plugin-node-resolve'
+import commonjs from 'rollup-plugin-commonjs'
+
+var pkg = require('./package.json')
+
+export default {
+  entry: 'yjs-dist.esm',
+  dest: 'yjs-dist.js',
+  moduleName: 'Y',
+  format: 'umd',
+  plugins: [
+    nodeResolve({
+      main: true,
+      module: true,
+      browser: true
+    }),
+    commonjs()
+  ],
+  sourceMap: true,
+  banner: `
+/**
+ * ${pkg.name} - ${pkg.description}
+ * @version v${pkg.version}
+ * @license ${pkg.license}
+ */
+`
+}

examples/serviceworker/index.html

@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <!-- quill does not include dist files! We are using the hosted version instead -->
+  <!--link rel="stylesheet" href="../bower_components/quill/dist/quill.snow.css" /-->
+  <link href="https://cdn.quilljs.com/1.0.4/quill.snow.css" rel="stylesheet">
+  <link href="//cdnjs.cloudflare.com/ajax/libs/KaTeX/0.5.1/katex.min.css" rel="stylesheet">
+  <link href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.2.0/styles/monokai-sublime.min.css" rel="stylesheet">
+  <style>
+    #quill-container {
+      border: 1px solid gray;
+      box-shadow: 0px 0px 10px gray;
+    }
+  </style>
+</head>
+<body>
+  <div id="quill-container">
+    <div id="quill">
+    </div>
+  </div>
+
+  <script src="//cdnjs.cloudflare.com/ajax/libs/KaTeX/0.5.1/katex.min.js" type="text/javascript"></script>
+  <script src="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.2.0/highlight.min.js" type="text/javascript"></script>
+  <script src="https://cdn.quilljs.com/1.0.4/quill.js"></script>
+  <!-- quill does not include dist files! We are using the hosted version instead (see above)
+  <script src="../bower_components/quill/dist/quill.js"></script>
+  -->
+  <script src="../bower_components/yjs/y.js"></script>
+  <script src="./index.js"></script>
+</body>
+</html>

examples/serviceworker/index.js

@@ -0,0 +1,49 @@
+/* global Y, Quill */
+
+// register yjs service worker
+if ('serviceWorker' in navigator) {
+  // Register service worker
+  // it is important to copy yjs-sw-template to the root directory!
+  navigator.serviceWorker.register('./yjs-sw-template.js').then(function (reg) {
+    console.log('Yjs service worker registration succeeded. Scope is ' + reg.scope)
+  }).catch(function (err) {
+    console.error('Yjs service worker registration failed with error ' + err)
+  })
+}
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'serviceworker',
+    room: 'ServiceWorkerExample2'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    richtext: 'Richtext' // y.share.richtext is of type Y.Richtext
+  }
+}).then(function (y) {
+  window.yServiceWorker = y
+
+  // create quill element
+  window.quill = new Quill('#quill', {
+    modules: {
+      formula: true,
+      syntax: true,
+      toolbar: [
+        [{ size: ['small', false, 'large', 'huge'] }],
+        ['bold', 'italic', 'underline'],
+        [{ color: [] }, { background: [] }],    // Snow theme fills in values
+        [{ script: 'sub' }, { script: 'super' }],
+        ['link', 'image'],
+        ['link', 'code-block'],
+        [{ list: 'ordered' }]
+      ]
+    },
+    theme: 'snow'
+  })
+  // bind quill to richtext type
+  y.share.richtext.bind(window.quill)
+})

examples/serviceworker/yjs-sw-template.js

@@ -0,0 +1,22 @@
+/* eslint-env worker */
+
+// copy and modify this file
+
+self.DBConfig = {
+  name: 'indexeddb'
+}
+self.ConnectorConfig = {
+  name: 'websockets-client',
+  // url: '..',
+  options: {
+    jsonp: false
+  }
+}
+
+importScripts(
+  '/bower_components/yjs/y.js',
+  '/bower_components/y-memory/y-memory.js',
+  '/bower_components/y-indexeddb/y-indexeddb.js',
+  '/bower_components/y-websockets-client/y-websockets-client.js',
+  '/bower_components/y-serviceworker/yjs-sw-include.js'
+)

examples/textarea/index.html

@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html>
+<body>
+  <textarea style="width:80%;" rows=40 id="textfield" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
+  <script src="../../y.js"></script>
+  <script src="../../../y-array/y-array.js"></script>
+  <script src="../../../y-text/y-text.js"></script>
+  <script src="../../../y-websockets-client/y-websockets-client.js"></script>
+  <script src="./index.js"></script>
+</body>
+</html>

examples/textarea/index.js

@@ -0,0 +1,23 @@
+/* global Y */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Textarea-example2',
+    // url: '//localhost:1234',
+    url: 'https://yjs-v13.herokuapp.com/'
+  },
+  share: {
+    textarea: 'Text'
+  },
+  timeout: 5000 // reject if no connection was established within 5 seconds
+}).then(function (y) {
+  window.yTextarea = y
+
+  // bind the textarea to a shared text element
+  y.share.textarea.bind(document.getElementById('textfield'))
+})

examples/xml/index.html

@@ -0,0 +1,40 @@
+<!DOCTYPE html>
+<html>
+</head>
+  <!-- jquery is not required for y-xml. It is just here for convenience, and to test batch operations. -->
+  <script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
+  <script src="../yjs-dist.js"></script>
+  <script src="./index.js"></script>
+</head>
+<body>
+  <h1> Shared DOM Example </h1>
+  <p> Use native DOM function or jQuery to manipulate the shared DOM (window.sharedDom). </p>
+  <div class="command">
+    <button type="button">Execute</button>
+    <input type="text" value='$(sharedDom).append("<h3>Appended headline</h3>")' size="40"/>
+  </div>
+  <div class="command">
+    <button type="button">Execute</button>
+    <input type="text" value='$(sharedDom).attr("align","right")' size="40"/>
+  </div>
+  <div class="command">
+    <button type="button">Execute</button>
+    <input type="text" value='$(sharedDom).attr("style","color:blue;")' size="40"/>
+  </div>
+
+  <script>
+    var commands = document.querySelectorAll(".command");
+    Array.prototype.forEach.call(document.querySelectorAll('.command'), function (command) {
+      var execute = function(){
+        eval(command.querySelector("input").value);
+      }
+      command.querySelector("button").onclick = execute
+      $(command.querySelector("input")).keyup(function (e) {
+        if (e.keyCode == 13) {
+          execute()
+        }
+      })
+    })
+  </script>
+</body>
+</html>

examples/xml/index.js

@@ -0,0 +1,23 @@
+/* global Y */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    // url: 'http://127.0.0.1:1234',
+    url: 'http://192.168.178.81:1234',
+    room: 'Xml-example'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    xml: 'Xml("p")' // y.share.xml is of type Y.Xml with tagname "p"
+  }
+}).then(function (y) {
+  window.yXml = y
+  // bind xml type to a dom, and put it in body
+  window.sharedDom = y.share.xml.getDom()
+  document.body.appendChild(window.sharedDom)
+})

examples/yjs-dist.esm

@@ -0,0 +1,7 @@
+
+import Y from '../src/Y.js'
+import yWebsocketsClient from '../../y-websockets-client/src/y-websockets-client.js'
+
+Y.extend(yWebsocketsClient)
+
+export default Y

gulpfile.helper.js

@@ -1,202 +0,0 @@
-
-var $ = require('gulp-load-plugins')()
-var minimist = require('minimist')
-var browserify = require('browserify')
-var source = require('vinyl-source-stream')
-var buffer = require('vinyl-buffer')
-
-module.exports = function (gulp, helperOptions) {
-  var runSequence = require('run-sequence').use(gulp)
-  var options = minimist(process.argv.slice(2), {
-    string: ['modulename', 'export', 'name', 'port', 'testfiles', 'es6'],
-    default: {
-      modulename: helperOptions.moduleName,
-      targetName: helperOptions.targetName,
-      export: 'ignore',
-      port: '8888',
-      testfiles: '**/*.spec.js',
-      es6: false,
-      browserify: helperOptions.browserify != null ? helperOptions.browserify : false,
-      includeRuntime: helperOptions.includeRuntime || false,
-      debug: false
-    }
-  })
-  if (options.es6 !== false) {
-    options.es6 = true
-  }
-  var files = {
-    dist: helperOptions.entry,
-    specs: helperOptions.specs,
-    src: './src/**/*.js'
-  }
-
-  if (options.includeRuntime) {
-    files.distEs5 = ['node_modules/regenerator/runtime.js', files.dist]
-  } else {
-    files.distEs5 = [files.dist]
-  }
-
-  gulp.task('dist:es5', function () {
-    var babelOptions = {
-      presets: ['es2015']
-    }
-    return (browserify({
-      entries: files.distEs5,
-      debug: true
-    }).transform('babelify', babelOptions)
-      .bundle()
-      .pipe(source(options.targetName))
-      .pipe(buffer())
-      .pipe($.sourcemaps.init({loadMaps: true}))
-      .pipe($.if(!options.debug, $.uglify().on('error', function (e) {
-        console.log('\x07', e.message, JSON.stringify(e)); return this.end()
-      })))
-      .pipe($.sourcemaps.write('.'))
-      .pipe(gulp.dest('./dist/')))
-  })
-
-  gulp.task('dist:es6', function () {
-    return (browserify({
-      entries: files.dist,
-      debug: true
-    }).bundle()
-      .pipe(source(options.targetName))
-      .pipe(buffer())
-      .pipe($.sourcemaps.init({loadMaps: true}))
-      // .pipe($.uglify()) -- generators not yet supported see #448
-      .pipe($.rename({
-        extname: '.es6'
-      }))
-      .pipe($.sourcemaps.write('.'))
-
-      .pipe(gulp.dest('./dist/')))
-  })
-
-  gulp.task('dist', ['dist:es6', 'dist:es5'])
-
-  gulp.task('watch:dist', function (cb) {
-    options.debug = true
-    gulp.src(['./README.md'])
-      .pipe($.watch('./README.md'))
-      .pipe(gulp.dest('./dist/'))
-    runSequence('dist', function () {
-      gulp.watch(files.src.concat('./README.md'), ['dist'])
-      cb()
-    })
-  })
-
-  gulp.task('dev:node', ['test'], function () {
-    gulp.watch(files.src, ['test'])
-  })
-
-  gulp.task('spec-build', function () {
-    var browserify = require('browserify')
-    var source = require('vinyl-source-stream')
-    var buffer = require('vinyl-buffer')
-
-    return browserify({
-      entries: files.specs, // .concat(files.distEs5),
-      debug: true
-    })// .transform('babelify', { presets: ['es2015'] })
-      .bundle()
-      .pipe(source('specs.js'))
-      .pipe(buffer())
-      // .pipe($.sourcemaps.init({loadMaps: true}))
-      // .pipe($.sourcemaps.write('.'))
-      .pipe(gulp.dest('./build/'))
-  })
-
-  gulp.task('dev:browser', ['spec-build'], function () {
-    gulp.watch(files.src, ['spec-build'])
-    return gulp.src('./build/specs.js')
-      .pipe($.jasmineBrowser.specRunner())
-      .pipe($.jasmineBrowser.server({port: options.port}))
-  })
-
-  gulp.task('test', function () {
-    return gulp.src(files.specs)
-      .pipe($.jasmine({
-        verbose: true,
-        includeStuckTrace: true
-      }))
-  })
-
-  gulp.task('updateSubmodule', function () {
-    return gulp.src('./package.json', {read: false})
-      .pipe($.shell([
-        'git submodule update --init',
-        'cd dist && git pull origin dist'
-      ]))
-  })
-
-  gulp.task('bump', function (cb) {
-    gulp.src(['./package.json', './bower.json', './dist/bower.json'], {base: '.'})
-      .pipe($.prompt.prompt({
-        type: 'checkbox',
-        name: 'bump',
-        message: 'What type of bump would you like to do?',
-        choices: ['patch', 'minor', 'major']
-      }, function (res) {
-        if (res.bump.length === 0) {
-          console.info('You have to select a bump type. Now I\'m going to use "patch" as bump type..')
-        }
-        var bumptype = res.bump[0]
-        if (bumptype === 'major') {
-          runSequence('bump_major', cb)
-        } else if (bumptype === 'minor') {
-          runSequence('bump_minor', cb)
-        } else {
-          runSequence('bump_patch', cb)
-        }
-      }))
-  })
-  gulp.task('bump_patch', function () {
-    return gulp.src(['./package.json', './bower.json', './dist/bower.json'], {base: '.'})
-      .pipe($.bump({type: 'patch'}))
-      .pipe(gulp.dest('./'))
-  })
-  gulp.task('bump_minor', function () {
-    return gulp.src(['./package.json', './bower.json', './dist/bower.json'], {base: '.'})
-      .pipe($.bump({type: 'minor'}))
-      .pipe(gulp.dest('./'))
-  })
-  gulp.task('bump_major', function () {
-    return gulp.src(['./package.json', './bower.json', './dist/bower.json'], {base: '.'})
-      .pipe($.bump({type: 'major'}))
-      .pipe(gulp.dest('./'))
-  })
-
-  gulp.task('publish_commits', function () {
-    return gulp.src('./package.json')
-        .pipe($.prompt.confirm({
-          message: 'Are you sure you want to publish this release?',
-          default: false
-        }))
-        .pipe($.shell([
-          'cp README.md dist',
-          'standard',
-          'echo "Deploying version <%= getVersion(file.path) %>"',
-          'git pull',
-          'cd ./dist/ && git add -A',
-          'cd ./dist/ && git commit -am "Deploy <%= getVersion(file.path) %>" -n',
-          'cd ./dist/ && git push origin HEAD:dist',
-          'cd ./dist/ && git tag -a v<%= getVersion(file.path) %> -m "Release <%= getVersion(file.path) %>"',
-          'cd ./dist/ && git push origin --tags',
-          'git commit -am "Release <%= getVersion(file.path) %>" -n',
-          'git push',
-          'npm publish',
-          'echo Finished'
-        ], {
-          templateData: {
-            getVersion: function () {
-              return JSON.parse(String.fromCharCode.apply(null, this.file._contents)).version
-            }
-          }
-        }))
-  })
-
-  gulp.task('publish', function (cb) {
-    /* TODO: include 'test',*/
-    runSequence('updateSubmodule', 'bump', 'dist', 'publish_commits', cb)
-  })
-}

gulpfile.js

@@ -1,104 +0,0 @@
-/* eslint-env node */
-
-/** Gulp Commands
-
-  gulp command*
-    [--export ModuleType]
-    [--name ModuleName]
-    [--testport TestPort]
-    [--testfiles TestFiles]
-
-  Module name (ModuleName):
-    Compile this to "y.js" (default)
-
-  Supported module types (ModuleType):
-    - amd
-    - amdStrict
-    - common
-    - commonStrict
-    - ignore (default)
-    - system
-    - umd
-    - umdStrict
-
-  Test port (TestPort):
-    Serve the specs on port 8888 (default)
-
-  Test files (TestFiles):
-    Specify which specs to use!
-
-  Commands:
-    - build:deploy
-        Build this library for deployment (es6->es5, minified)
-    - dev:browser
-        Watch the ./src directory.
-        Builds the library on changes.
-        Starts an http-server and serves the test suite on http://127.0.0.1:8888.
-    - dev:node
-        Watch the ./src directory.
-        Builds and specs the library on changes.
-        Usefull to run with node-inspector.
-        `node-debug $(which gulp) dev:node
-    - test:
-        Test this library
-*/
-
-var gulp = require('gulp')
-var $ = require('gulp-load-plugins')()
-var runSequence = require('run-sequence').use(gulp)
-
-require('./gulpfile.helper.js')(gulp, {
-  polyfills: [],
-  entry: './src/y.js',
-  targetName: 'y.js',
-  moduleName: 'yjs',
-  includeRuntime: true,
-  specs: [
-    './src/Database.spec.js',
-    '../y-array/src/Array.spec.js',
-    '../y-map/src/Map.spec.js'
-  ]
-})
-
-gulp.task('dev:examples', ['watch:dist'], function () {
-  // watch all distfiles and copy them to bower_components
-  var distfiles = ['./dist/*.{js,es6}', './dist/*.{js,es6}.map', '../y-*/dist/*.{js,es6}', '../y-*/dist/*.{js,es6}.map']
-  gulp.src(distfiles)
-    .pipe($.watch(distfiles))
-    .pipe($.rename(function (path) {
-      var dir = path.dirname.split(/[\\\/]/)[0]
-      console.log(JSON.stringify(path))
-      path.dirname = dir === '.' ? 'yjs' : dir
-    }))
-    .pipe(gulp.dest('./dist/Examples/bower_components/'))
-
-  return $.serve('dist/Examples/')()
-})
-
-gulp.task('default', ['updateSubmodule'], function (cb) {
-  gulp.src('package.json')
-    .pipe($.prompt.prompt({
-      type: 'checkbox',
-      name: 'tasks',
-      message: 'Which tasks would you like to run?',
-      choices: [
-        'test                    Test this project',
-        'dev:examples            Serve the examples directory in ./dist/',
-        'dev:browser             Watch files & serve the testsuite for the browser',
-        'dev:nodejs              Watch filse & test this project with nodejs',
-        'bump                    Bump the current state of the project',
-        'publish                 Publish this project. Creates a github tag',
-        'dist                    Build the distribution files'
-      ]
-    }, function (res) {
-      var tasks = res.tasks.map(function (task) {
-        return task.split(' ')[0]
-      })
-      if (tasks.length > 0) {
-        console.info('gulp ' + tasks.join(' '))
-        runSequence(tasks, cb)
-      } else {
-        console.info('Ok, .. goodbye')
-      }
-    }))
-})

package.json

@@ -1,24 +1,26 @@
 {
   "name": "yjs",
-  "version": "11.2.5",
-  "description": "A framework for real-time p2p shared editing on arbitrary complex data types",
-  "main": "./src/y.js",
+  "version": "13.0.0-30",
+  "description": "A framework for real-time p2p shared editing on any data",
+  "main": "./y.node.js",
+  "browser": "./y.js",
+  "module": "./src/y.js",
   "scripts": {
-    "test": "node --harmony ./node_modules/.bin/gulp test",
-    "lint": "./node_modules/.bin/standard"
+    "test": "npm run lint",
+    "debug": "concurrently 'rollup -wc rollup.test.js' 'cutest-serve y.test.js -o'",
+    "lint": "standard",
+    "dist": "rollup -c rollup.browser.js; rollup -c rollup.node.js",
+    "watch": "concurrently 'rollup -wc rollup.browser.js' 'rollup -wc rollup.node.js'",
+    "postversion": "npm run dist",
+    "postpublish": "tag-dist-files --overwrite-existing-tag"
   },
-  "pre-commit": [
-    "lint",
-    "test"
+  "files": [
+    "y.*"
   ],
   "standard": {
-    "parser": "babel-eslint",
     "ignore": [
-      "build/**",
-      "dist/**",
-      "declarations/**",
-      "./y.js",
-      "./y.js.map"
+      "/y.js",
+      "/y.js.map"
     ]
   },
   "repository": {
@@ -42,38 +44,29 @@
   },
   "homepage": "http://y-js.org",
   "devDependencies": {
-    "babel-eslint": "^5.0.0-beta6",
-    "babel-plugin-transform-runtime": "^6.1.18",
-    "babel-preset-es2015": "^6.1.18",
-    "babelify": "^7.2.0",
-    "browserify": "^12.0.1",
-    "eslint": "^1.10.2",
-    "gulp": "^3.9.0",
-    "gulp-bump": "^1.0.0",
-    "gulp-concat": "^2.6.0",
-    "gulp-filter": "^3.0.1",
-    "gulp-git": "^1.6.0",
-    "gulp-if": "^2.0.0",
-    "gulp-jasmine": "^2.0.1",
-    "gulp-jasmine-browser": "^0.2.3",
-    "gulp-load-plugins": "^1.0.0",
-    "gulp-prompt": "^0.1.2",
-    "gulp-rename": "^1.2.2",
-    "gulp-serve": "^1.2.0",
-    "gulp-shell": "^0.5.1",
-    "gulp-sourcemaps": "^1.5.2",
-    "gulp-tag-version": "^1.3.0",
-    "gulp-uglify": "1.4.*",
-    "gulp-util": "^3.0.6",
-    "gulp-watch": "^4.3.5",
-    "minimist": "^1.2.0",
-    "pre-commit": "^1.1.1",
-    "regenerator": "^0.8.42",
-    "run-sequence": "^1.1.4",
-    "seedrandom": "^2.4.2",
-    "standard": "^5.2.2",
-    "vinyl-buffer": "^1.0.0",
-    "vinyl-source-stream": "^1.1.0"
+    "babel-cli": "^6.24.1",
+    "babel-plugin-external-helpers": "^6.22.0",
+    "babel-plugin-transform-regenerator": "^6.24.1",
+    "babel-plugin-transform-runtime": "^6.23.0",
+    "babel-preset-latest": "^6.24.1",
+    "chance": "^1.0.9",
+    "concurrently": "^3.4.0",
+    "cutest": "^0.1.9",
+    "rollup-plugin-babel": "^2.7.1",
+    "rollup-plugin-commonjs": "^8.0.2",
+    "rollup-plugin-inject": "^2.0.0",
+    "rollup-plugin-multi-entry": "^2.0.1",
+    "rollup-plugin-node-resolve": "^3.0.0",
+    "rollup-plugin-uglify": "^1.0.2",
+    "rollup-regenerator-runtime": "^6.23.1",
+    "rollup-watch": "^3.2.2",
+    "standard": "^10.0.2",
+    "tag-dist-files": "^0.1.6"
   },
-  "dependencies": {}
+  "dependencies": {
+    "debug": "^2.6.8",
+    "fast-diff": "^1.1.2",
+    "utf-8": "^1.0.0",
+    "utf8": "^2.1.2"
+  }
 }

rollup.browser.js

@@ -0,0 +1,46 @@
+import babel from 'rollup-plugin-babel'
+import uglify from 'rollup-plugin-uglify'
+import nodeResolve from 'rollup-plugin-node-resolve'
+import commonjs from 'rollup-plugin-commonjs'
+var pkg = require('./package.json')
+
+export default {
+  input: 'src/Y.js',
+  name: 'Y',
+  sourcemap: true,
+  output: {
+    file: 'y.js',
+    format: 'umd'
+  },
+  plugins: [
+    nodeResolve({
+      main: true,
+      module: true,
+      browser: true
+    }),
+    commonjs(),
+    babel(),
+    uglify({
+      mangle: {
+        except: ['YMap', 'Y', 'YArray', 'YText', 'YXmlFragment', 'YXmlElement', 'YXmlEvent', 'YXmlText', 'YEvent', 'YArrayEvent', 'YMapEvent', 'Type', 'Delete', 'ItemJSON', 'ItemString', 'Item']
+      },
+      output: {
+        comments: function (node, comment) {
+          var text = comment.value
+          var type = comment.type
+          if (type === 'comment2') {
+            // multiline comment
+            return /@license/i.test(text)
+          }
+        }
+      }
+    })
+  ],
+  banner: `
+/**
+ * ${pkg.name} - ${pkg.description}
+ * @version v${pkg.version}
+ * @license ${pkg.license}
+ */
+`
+}

rollup.node.js

@@ -0,0 +1,28 @@
+import nodeResolve from 'rollup-plugin-node-resolve'
+import commonjs from 'rollup-plugin-commonjs'
+var pkg = require('./package.json')
+
+export default {
+  input: 'src/y-dist.cjs.js',
+  nameame: 'Y',
+  sourcemap: true,
+  output: {
+    file: 'y.node.js',
+    format: 'cjs'
+  },
+  plugins: [
+    nodeResolve({
+      main: true,
+      module: true,
+      browser: true
+    }),
+    commonjs()
+  ],
+  banner: `
+/**
+ * ${pkg.name} - ${pkg.description}
+ * @version v${pkg.version}
+ * @license ${pkg.license}
+ */
+`
+}

rollup.test.js

@@ -0,0 +1,22 @@
+import nodeResolve from 'rollup-plugin-node-resolve'
+import commonjs from 'rollup-plugin-commonjs'
+import multiEntry from 'rollup-plugin-multi-entry'
+
+export default {
+  input: 'test/y-xml.tests.js',
+  name: 'y-tests',
+  sourcemap: true,
+  output: {
+    file: 'y.test.js',
+    format: 'umd'
+  },
+  plugins: [
+    nodeResolve({
+      main: true,
+      module: true,
+      browser: true
+    }),
+    commonjs(),
+    multiEntry()
+  ]
+}

src/Binary/Decoder.js

@@ -0,0 +1,120 @@
+import utf8 from 'utf-8'
+import ID from '../Util/ID.js'
+import { default as RootID, RootFakeUserID } from '../Util/RootID.js'
+
+export default class BinaryDecoder {
+  constructor (buffer) {
+    if (buffer instanceof ArrayBuffer) {
+      this.uint8arr = new Uint8Array(buffer)
+    } else if (buffer instanceof Uint8Array || (typeof Buffer !== 'undefined' && buffer instanceof Buffer)) {
+      this.uint8arr = buffer
+    } else {
+      throw new Error('Expected an ArrayBuffer or Uint8Array!')
+    }
+    this.pos = 0
+  }
+  /**
+   * Clone this decoder instance
+   * Optionally set a new position parameter
+   */
+  clone (newPos = this.pos) {
+    let decoder = new BinaryDecoder(this.uint8arr)
+    decoder.pos = newPos
+    return decoder
+  }
+  /**
+   * Number of bytes
+   */
+  get length () {
+    return this.uint8arr.length
+  }
+  /**
+   * Skip one byte, jump to the next position
+   */
+  skip8 () {
+    this.pos++
+  }
+  /**
+   * Read one byte as unsigned integer
+   */
+  readUint8 () {
+    return this.uint8arr[this.pos++]
+  }
+  /**
+   * Read 4 bytes as unsigned integer
+   */
+  readUint32 () {
+    let uint =
+      this.uint8arr[this.pos] +
+      (this.uint8arr[this.pos + 1] << 8) +
+      (this.uint8arr[this.pos + 2] << 16) +
+      (this.uint8arr[this.pos + 3] << 24)
+    this.pos += 4
+    return uint
+  }
+  /**
+   * Look ahead without incrementing position
+   * to the next byte and read it as unsigned integer
+   */
+  peekUint8 () {
+    return this.uint8arr[this.pos]
+  }
+  /**
+   * Read unsigned integer (32bit) with variable length
+   * 1/8th of the storage is used as encoding overhead
+   *  - numbers < 2^7 is stored in one byte
+   *  - numbers < 2^14 is stored in two bytes
+   *  ..
+   */
+  readVarUint () {
+    let num = 0
+    let len = 0
+    while (true) {
+      let r = this.uint8arr[this.pos++]
+      num = num | ((r & 0b1111111) << len)
+      len += 7
+      if (r < 1 << 7) {
+        return num >>> 0 // return unsigned number!
+      }
+      if (len > 35) {
+        throw new Error('Integer out of range!')
+      }
+    }
+  }
+  /**
+   * Read string of variable length
+   * - varUint is used to store the length of the string
+   */
+  readVarString () {
+    let len = this.readVarUint()
+    let bytes = new Array(len)
+    for (let i = 0; i < len; i++) {
+      bytes[i] = this.uint8arr[this.pos++]
+    }
+    return utf8.getStringFromBytes(bytes)
+  }
+  /**
+   *  Look ahead and read varString without incrementing position
+   */
+  peekVarString () {
+    let pos = this.pos
+    let s = this.readVarString()
+    this.pos = pos
+    return s
+  }
+  /**
+   * Read ID
+   * - If first varUint read is 0xFFFFFF a RootID is returned
+   * - Otherwise an ID is returned
+   */
+  readID () {
+    let user = this.readVarUint()
+    if (user === RootFakeUserID) {
+      // read property name and type id
+      const rid = new RootID(this.readVarString(), null)
+      rid.type = this.readVarUint()
+      return rid
+    }
+    return new ID(user, this.readVarUint())
+  }
+}

src/Binary/Encoder.js

@@ -0,0 +1,83 @@
+import utf8 from 'utf-8'
+import { RootFakeUserID } from '../Util/RootID.js'
+
+const bits7 = 0b1111111
+const bits8 = 0b11111111
+
+export default class BinaryEncoder {
+  constructor () {
+    // TODO: implement chained Uint8Array buffers instead of Array buffer
+    this.data = []
+  }
+
+  get length () {
+    return this.data.length
+  }
+
+  get pos () {
+    return this.data.length
+  }
+
+  createBuffer () {
+    return Uint8Array.from(this.data).buffer
+  }
+
+  writeUint8 (num) {
+    this.data.push(num & bits8)
+  }
+
+  setUint8 (pos, num) {
+    this.data[pos] = num & bits8
+  }
+
+  writeUint16 (num) {
+    this.data.push(num & bits8, (num >>> 8) & bits8)
+  }
+
+  setUint16 (pos, num) {
+    this.data[pos] = num & bits8
+    this.data[pos + 1] = (num >>> 8) & bits8
+  }
+
+  writeUint32 (num) {
+    for (let i = 0; i < 4; i++) {
+      this.data.push(num & bits8)
+      num >>>= 8
+    }
+  }
+
+  setUint32 (pos, num) {
+    for (let i = 0; i < 4; i++) {
+      this.data[pos + i] = num & bits8
+      num >>>= 8
+    }
+  }
+
+  writeVarUint (num) {
+    while (num >= 0b10000000) {
+      this.data.push(0b10000000 | (bits7 & num))
+      num >>>= 7
+    }
+    this.data.push(bits7 & num)
+  }
+
+  writeVarString (str) {
+    let bytes = utf8.setBytesFromString(str)
+    let len = bytes.length
+    this.writeVarUint(len)
+    for (let i = 0; i < len; i++) {
+      this.data.push(bytes[i])
+    }
+  }
+
+  writeID (id) {
+    const user = id.user
+    this.writeVarUint(user)
+    if (user !== RootFakeUserID) {
+      this.writeVarUint(id.clock)
+    } else {
+      this.writeVarString(id.name)
+      this.writeVarUint(id.type)
+    }
+  }
+}

src/Connector.js

@@ -1,414 +1,294 @@
-/* @flow */
-'use strict'
+import BinaryEncoder from './Binary/Encoder.js'
+import BinaryDecoder from './Binary/Decoder.js'
 
-module.exports = function (Y/* :any */) {
-  class AbstractConnector {
-    /* ::
-    y: YConfig;
-    role: SyncRole;
-    connections: Object;
-    isSynced: boolean;
-    userEventListeners: Array<Function>;
-    whenSyncedListeners: Array<Function>;
-    currentSyncTarget: ?UserId;
-    syncingClients: Array<UserId>;
-    forwardToSyncingClients: boolean;
-    debug: boolean;
-    broadcastedHB: boolean;
-    syncStep2: Promise;
-    userId: UserId;
-    send: Function;
-    broadcast: Function;
-    broadcastOpBuffer: Array<Operation>;
-    protocolVersion: number;
-    */
-    /*
-      opts contains the following information:
-       role : String Role of this client ("master" or "slave")
-       userId : String Uniquely defines the user.
-       debug: Boolean Whether to print debug messages (optional)
-    */
-    constructor (y, opts) {
-      this.y = y
-      if (opts == null) {
-        opts = {}
-      }
-      if (opts.role == null || opts.role === 'master') {
-        this.role = 'master'
-      } else if (opts.role === 'slave') {
-        this.role = 'slave'
-      } else {
-        throw new Error("Role must be either 'master' or 'slave'!")
-      }
-      this.y.db.forwardAppliedOperations = opts.forwardAppliedOperations || false
-      this.role = opts.role
-      this.connections = {}
-      this.isSynced = false
-      this.userEventListeners = []
-      this.whenSyncedListeners = []
-      this.currentSyncTarget = null
-      this.syncingClients = []
-      this.forwardToSyncingClients = opts.forwardToSyncingClients !== false
-      this.debug = opts.debug === true
-      this.broadcastedHB = false
-      this.syncStep2 = Promise.resolve()
-      this.broadcastOpBuffer = []
-      this.protocolVersion = 11
+import { sendSyncStep1, readSyncStep1 } from './MessageHandler/syncStep1.js'
+import { readSyncStep2 } from './MessageHandler/syncStep2.js'
+import { integrateRemoteStructs } from './MessageHandler/integrateRemoteStructs.js'
+
+import debug from 'debug'
+
+export default class AbstractConnector {
+  constructor (y, opts) {
+    this.y = y
+    this.opts = opts
+    if (opts.role == null || opts.role === 'master') {
+      this.role = 'master'
+    } else if (opts.role === 'slave') {
+      this.role = 'slave'
+    } else {
+      throw new Error("Role must be either 'master' or 'slave'!")
     }
-    reconnect () {
+    this.log = debug('y:connector')
+    this.logMessage = debug('y:connector-message')
+    this._forwardAppliedStructs = opts.forwardAppliedOperations || false // TODO: rename
+    this.role = opts.role
+    this.connections = new Map()
+    this.isSynced = false
+    this.userEventListeners = []
+    this.whenSyncedListeners = []
+    this.currentSyncTarget = null
+    this.debug = opts.debug === true
+    this.broadcastBuffer = new BinaryEncoder()
+    this.broadcastBufferSize = 0
+    this.protocolVersion = 11
+    this.authInfo = opts.auth || null
+    this.checkAuth = opts.checkAuth || function () { return Promise.resolve('write') } // default is everyone has write access
+    if (opts.maxBufferLength == null) {
+      this.maxBufferLength = -1
+    } else {
+      this.maxBufferLength = opts.maxBufferLength
     }
-    disconnect () {
-      this.connections = {}
-      this.isSynced = false
-      this.currentSyncTarget = null
-      this.broadcastedHB = false
-      this.syncingClients = []
-      this.whenSyncedListeners = []
-      return this.y.db.stopGarbageCollector()
-    }
-    setUserId (userId) {
-      if (this.userId == null) {
-        this.userId = userId
-        return this.y.db.setUserId(userId)
-      } else {
-        return null
-      }
-    }
-    onUserEvent (f) {
-      this.userEventListeners.push(f)
-    }
-    userLeft (user) {
-      if (this.connections[user] != null) {
-        delete this.connections[user]
-        if (user === this.currentSyncTarget) {
-          this.currentSyncTarget = null
-          this.findNextSyncTarget()
-        }
-        this.syncingClients = this.syncingClients.filter(function (cli) {
-          return cli !== user
-        })
-        for (var f of this.userEventListeners) {
-          f({
-            action: 'userLeft',
-            user: user
-          })
-        }
-      }
-    }
-    userJoined (user, role) {
-      if (role == null) {
-        throw new Error('You must specify the role of the joined user!')
-      }
-      if (this.connections[user] != null) {
-        throw new Error('This user already joined!')
-      }
-      this.connections[user] = {
-        isSynced: false,
-        role: role
-      }
+  }
+
+  reconnect () {
+    this.log('reconnecting..')
+  }
+
+  disconnect () {
+    this.log('discronnecting..')
+    this.connections = new Map()
+    this.isSynced = false
+    this.currentSyncTarget = null
+    this.whenSyncedListeners = []
+    return Promise.resolve()
+  }
+
+  onUserEvent (f) {
+    this.userEventListeners.push(f)
+  }
+
+  removeUserEventListener (f) {
+    this.userEventListeners = this.userEventListeners.filter(g => f !== g)
+  }
+
+  userLeft (user) {
+    if (this.connections.has(user)) {
+      this.log('%s: User left %s', this.y.userID, user)
+      this.connections.delete(user)
+      // check if isSynced event can be sent now
+      this._setSyncedWith(null)
       for (var f of this.userEventListeners) {
         f({
-          action: 'userJoined',
-          user: user,
-          role: role
+          action: 'userLeft',
+          user: user
         })
       }
-      if (this.currentSyncTarget == null) {
-        this.findNextSyncTarget()
-      }
-    }
-    // Execute a function _when_ we are connected.
-    // If not connected, wait until connected
-    whenSynced (f) {
-      if (this.isSynced) {
-        f()
-      } else {
-        this.whenSyncedListeners.push(f)
-      }
-    }
-    /*
-
-     returns false, if there is no sync target
-     true otherwise
-    */
-    findNextSyncTarget () {
-      if (this.currentSyncTarget != null || this.isSynced) {
-        return // "The current sync has not finished!"
-      }
-
-      var syncUser = null
-      for (var uid in this.connections) {
-        if (!this.connections[uid].isSynced) {
-          syncUser = uid
-          break
-        }
-      }
-      var conn = this
-      if (syncUser != null) {
-        this.currentSyncTarget = syncUser
-        this.y.db.requestTransaction(function *() {
-          var stateSet = yield* this.getStateSet()
-          var deleteSet = yield* this.getDeleteSet()
-          conn.send(syncUser, {
-            type: 'sync step 1',
-            stateSet: stateSet,
-            deleteSet: deleteSet,
-            protocolVersion: conn.protocolVersion
-          })
-        })
-      } else {
-        this.y.db.requestTransaction(function *() {
-          // it is crucial that isSynced is set at the time garbageCollectAfterSync is called
-          conn.isSynced = true
-          yield* this.garbageCollectAfterSync()
-          // call whensynced listeners
-          for (var f of conn.whenSyncedListeners) {
-            f()
-          }
-          conn.whenSyncedListeners = []
-        })
-      }
-    }
-    send (uid, message) {
-      if (this.debug) {
-        console.log(`send ${this.userId} -> ${uid}: ${message.type}`, message) // eslint-disable-line
-      }
-    }
-    /*
-      Buffer operations, and broadcast them when ready.
-    */
-    broadcastOps (ops) {
-      ops = ops.map(function (op) {
-        return Y.Struct[op.struct].encode(op)
-      })
-      var self = this
-      function broadcastOperations () {
-        if (self.broadcastOpBuffer.length > 0) {
-          self.broadcast({
-            type: 'update',
-            ops: self.broadcastOpBuffer
-          })
-          self.broadcastOpBuffer = []
-        }
-      }
-      if (this.broadcastOpBuffer.length === 0) {
-        this.broadcastOpBuffer = ops
-        if (this.y.db.transactionInProgress) {
-          this.y.db.whenTransactionsFinished().then(broadcastOperations)
-        } else {
-          setTimeout(broadcastOperations, 0)
-        }
-      } else {
-        this.broadcastOpBuffer = this.broadcastOpBuffer.concat(ops)
-      }
-    }
-    /*
-      You received a raw message, and you know that it is intended for Yjs. Then call this function.
-    */
-    receiveMessage (sender/* :UserId */, message/* :Message */) {
-      if (sender === this.userId) {
-        return
-      }
-      if (this.debug) {
-        console.log(`receive ${sender} -> ${this.userId}: ${message.type}`, JSON.parse(JSON.stringify(message))) // eslint-disable-line
-      }
-      if (message.protocolVersion != null && message.protocolVersion !== this.protocolVersion) {
-        console.error(
-          `You tried to sync with a yjs instance that has a different protocol version
-          (You: ${this.protocolVersion}, Client: ${message.protocolVersion}).
-          The sync was stopped. You need to upgrade your dependencies (especially Yjs & the Connector)!
-          `)
-        this.send(sender, {
-          type: 'sync stop',
-          protocolVersion: this.protocolVersion
-        })
-        return
-      }
-      if (message.type === 'sync step 1') {
-        let conn = this
-        let m = message
-        this.y.db.requestTransaction(function *() {
-          var currentStateSet = yield* this.getStateSet()
-          yield* this.applyDeleteSet(m.deleteSet)
-
-          var ds = yield* this.getDeleteSet()
-          var ops = yield* this.getOperations(m.stateSet)
-          conn.send(sender, {
-            type: 'sync step 2',
-            os: ops,
-            stateSet: currentStateSet,
-            deleteSet: ds,
-            protocolVersion: this.protocolVersion
-          })
-          if (this.forwardToSyncingClients) {
-            conn.syncingClients.push(sender)
-            setTimeout(function () {
-              conn.syncingClients = conn.syncingClients.filter(function (cli) {
-                return cli !== sender
-              })
-              conn.send(sender, {
-                type: 'sync done'
-              })
-            }, 5000) // TODO: conn.syncingClientDuration)
-          } else {
-            conn.send(sender, {
-              type: 'sync done'
-            })
-          }
-          conn._setSyncedWith(sender)
-        })
-      } else if (message.type === 'sync step 2') {
-        let conn = this
-        var broadcastHB = !this.broadcastedHB
-        this.broadcastedHB = true
-        var db = this.y.db
-        var defer = {}
-        defer.promise = new Promise(function (resolve) {
-          defer.resolve = resolve
-        })
-        this.syncStep2 = defer.promise
-        let m /* :MessageSyncStep2 */ = message
-        db.requestTransaction(function * () {
-          yield* this.applyDeleteSet(m.deleteSet)
-          this.store.apply(m.os)
-          db.requestTransaction(function * () {
-            var ops = yield* this.getOperations(m.stateSet)
-            if (ops.length > 0) {
-              if (!broadcastHB) { // TODO: consider to broadcast here..
-                conn.send(sender, {
-                  type: 'update',
-                  ops: ops
-                })
-              } else {
-                // broadcast only once!
-                conn.broadcastOps(ops)
-              }
-            }
-            defer.resolve()
-          })
-        })
-      } else if (message.type === 'sync done') {
-        var self = this
-        this.syncStep2.then(function () {
-          self._setSyncedWith(sender)
-        })
-      } else if (message.type === 'update') {
-        if (this.forwardToSyncingClients) {
-          for (var client of this.syncingClients) {
-            this.send(client, message)
-          }
-        }
-        if (this.y.db.forwardAppliedOperations) {
-          var delops = message.ops.filter(function (o) {
-            return o.struct === 'Delete'
-          })
-          if (delops.length > 0) {
-            this.broadcastOps(delops)
-          }
-        }
-        this.y.db.apply(message.ops)
-      }
-    }
-    _setSyncedWith (user) {
-      var conn = this.connections[user]
-      if (conn != null) {
-        conn.isSynced = true
-      }
-      if (user === this.currentSyncTarget) {
-        this.currentSyncTarget = null
-        this.findNextSyncTarget()
-      }
-    }
-    /*
-      Currently, the HB encodes operations as JSON. For the moment I want to keep it
-      that way. Maybe we support encoding in the HB as XML in the future, but for now I don't want
-      too much overhead. Y is very likely to get changed a lot in the future
-
-      Because we don't want to encode JSON as string (with character escaping, wich makes it pretty much unreadable)
-      we encode the JSON as XML.
-
-      When the HB support encoding as XML, the format should look pretty much like this.
-
-      does not support primitive values as array elements
-      expects an ltx (less than xml) object
-    */
-    parseMessageFromXml (m/* :any */) {
-      function parseArray (node) {
-        for (var n of node.children) {
-          if (n.getAttribute('isArray') === 'true') {
-            return parseArray(n)
-          } else {
-            return parseObject(n)
-          }
-        }
-      }
-      function parseObject (node/* :any */) {
-        var json = {}
-        for (var attrName in node.attrs) {
-          var value = node.attrs[attrName]
-          var int = parseInt(value, 10)
-          if (isNaN(int) || ('' + int) !== value) {
-            json[attrName] = value
-          } else {
-            json[attrName] = int
-          }
-        }
-        for (var n/* :any */ in node.children) {
-          var name = n.name
-          if (n.getAttribute('isArray') === 'true') {
-            json[name] = parseArray(n)
-          } else {
-            json[name] = parseObject(n)
-          }
-        }
-        return json
-      }
-      parseObject(m)
-    }
-    /*
-      encode message in xml
-      we use string because Strophe only accepts an "xml-string"..
-      So {a:4,b:{c:5}} will look like
-      <y a="4">
-        <b c="5"></b>
-      </y>
-      m - ltx element
-      json - Object
-    */
-    encodeMessageToXml (msg, obj) {
-      // attributes is optional
-      function encodeObject (m, json) {
-        for (var name in json) {
-          var value = json[name]
-          if (name == null) {
-            // nop
-          } else if (value.constructor === Object) {
-            encodeObject(m.c(name), value)
-          } else if (value.constructor === Array) {
-            encodeArray(m.c(name), value)
-          } else {
-            m.setAttribute(name, value)
-          }
-        }
-      }
-      function encodeArray (m, array) {
-        m.setAttribute('isArray', 'true')
-        for (var e of array) {
-          if (e.constructor === Object) {
-            encodeObject(m.c('array-element'), e)
-          } else {
-            encodeArray(m.c('array-element'), e)
-          }
-        }
-      }
-      if (obj.constructor === Object) {
-        encodeObject(msg.c('y', { xmlns: 'http://y.ninja/connector-stanza' }), obj)
-      } else if (obj.constructor === Array) {
-        encodeArray(msg.c('y', { xmlns: 'http://y.ninja/connector-stanza' }), obj)
-      } else {
-        throw new Error("I can't encode this json!")
-      }
     }
   }
-  Y.AbstractConnector = AbstractConnector
+
+  userJoined (user, role, auth) {
+    if (role == null) {
+      throw new Error('You must specify the role of the joined user!')
+    }
+    if (this.connections.has(user)) {
+      throw new Error('This user already joined!')
+    }
+    this.log('%s: User joined %s', this.y.userID, user)
+    this.connections.set(user, {
+      uid: user,
+      isSynced: false,
+      role: role,
+      processAfterAuth: [],
+      processAfterSync: [],
+      auth: auth || null,
+      receivedSyncStep2: false
+    })
+    let defer = {}
+    defer.promise = new Promise(function (resolve) { defer.resolve = resolve })
+    this.connections.get(user).syncStep2 = defer
+    for (var f of this.userEventListeners) {
+      f({
+        action: 'userJoined',
+        user: user,
+        role: role
+      })
+    }
+    this._syncWithUser(user)
+  }
+
+  // Execute a function _when_ we are connected.
+  // If not connected, wait until connected
+  whenSynced (f) {
+    if (this.isSynced) {
+      f()
+    } else {
+      this.whenSyncedListeners.push(f)
+    }
+  }
+
+  _syncWithUser (userID) {
+    if (this.role === 'slave') {
+      return // "The current sync has not finished or this is controlled by a master!"
+    }
+    sendSyncStep1(this, userID)
+  }
+
+  _fireIsSyncedListeners () {
+    if (!this.isSynced) {
+      this.isSynced = true
+      // It is safer to remove this!
+      // call whensynced listeners
+      for (var f of this.whenSyncedListeners) {
+        f()
+      }
+      this.whenSyncedListeners = []
+      this.y.emit('synced')
+    }
+  }
+
+  send (uid, buffer) {
+    const y = this.y
+    if (!(buffer instanceof ArrayBuffer || buffer instanceof Uint8Array)) {
+      throw new Error('Expected Message to be an ArrayBuffer or Uint8Array - don\'t use this method to send custom messages')
+    }
+    this.log('User%s to User%s: Send \'%y\'', y.userID, uid, buffer)
+    this.logMessage('User%s to User%s: Send %Y', y.userID, uid, [y, buffer])
+  }
+
+  broadcast (buffer) {
+    const y = this.y
+    if (!(buffer instanceof ArrayBuffer || buffer instanceof Uint8Array)) {
+      throw new Error('Expected Message to be an ArrayBuffer or Uint8Array - don\'t use this method to send custom messages')
+    }
+    this.log('User%s: Broadcast \'%y\'', y.userID, buffer)
+    this.logMessage('User%s: Broadcast: %Y', y.userID, [y, buffer])
+  }
+
+  /*
+    Buffer operations, and broadcast them when ready.
+  */
+  broadcastStruct (struct) {
+    const firstContent = this.broadcastBuffer.length === 0
+    if (firstContent) {
+      this.broadcastBuffer.writeVarString(this.y.room)
+      this.broadcastBuffer.writeVarString('update')
+      this.broadcastBufferSize = 0
+      this.broadcastBufferSizePos = this.broadcastBuffer.pos
+      this.broadcastBuffer.writeUint32(0)
+    }
+    this.broadcastBufferSize++
+    struct._toBinary(this.broadcastBuffer)
+    if (this.maxBufferLength > 0 && this.broadcastBuffer.length > this.maxBufferLength) {
+      // it is necessary to send the buffer now
+      // cache the buffer and check if server is responsive
+      const buffer = this.broadcastBuffer
+      buffer.setUint32(this.broadcastBufferSizePos, this.broadcastBufferSize)
+      this.broadcastBuffer = new BinaryEncoder()
+      this.whenRemoteResponsive().then(() => {
+        this.broadcast(buffer.createBuffer())
+      })
+    } else if (firstContent) {
+      // send the buffer when all transactions are finished
+      // (or buffer exceeds maxBufferLength)
+      setTimeout(() => {
+        if (this.broadcastBuffer.length > 0) {
+          const buffer = this.broadcastBuffer
+          buffer.setUint32(this.broadcastBufferSizePos, this.broadcastBufferSize)
+          this.broadcast(buffer.createBuffer())
+          this.broadcastBuffer = new BinaryEncoder()
+        }
+      }, 0)
+    }
+  }
+
+  /*
+   * Somehow check the responsiveness of the remote clients/server
+   * Default behavior:
+   *   Wait 100ms before broadcasting the next batch of operations
+   *
+   * Only used when maxBufferLength is set
+   *
+   */
+  whenRemoteResponsive () {
+    return new Promise(function (resolve) {
+      setTimeout(resolve, 100)
+    })
+  }
+
+  /*
+    You received a raw message, and you know that it is intended for Yjs. Then call this function.
+  */
+  receiveMessage (sender, buffer, skipAuth) {
+    const y = this.y
+    const userID = y.userID
+    skipAuth = skipAuth || false
+    if (!(buffer instanceof ArrayBuffer || buffer instanceof Uint8Array)) {
+      return Promise.reject(new Error('Expected Message to be an ArrayBuffer or Uint8Array!'))
+    }
+    if (sender === userID) {
+      return Promise.resolve()
+    }
+    let decoder = new BinaryDecoder(buffer)
+    let encoder = new BinaryEncoder()
+    let roomname = decoder.readVarString() // read room name
+    encoder.writeVarString(roomname)
+    let messageType = decoder.readVarString()
+    let senderConn = this.connections.get(sender)
+    this.log('User%s from User%s: Receive \'%s\'', userID, sender, messageType)
+    this.logMessage('User%s from User%s: Receive %Y', userID, sender, [y, buffer])
+    if (senderConn == null && !skipAuth) {
+      throw new Error('Received message from unknown peer!')
+    }
+    if (messageType === 'sync step 1' || messageType === 'sync step 2') {
+      let auth = decoder.readVarUint()
+      if (senderConn.auth == null) {
+        senderConn.processAfterAuth.push([messageType, senderConn, decoder, encoder, sender])
+        // check auth
+        return this.checkAuth(auth, y, sender).then(authPermissions => {
+          if (senderConn.auth == null) {
+            senderConn.auth = authPermissions
+            y.emit('userAuthenticated', {
+              user: senderConn.uid,
+              auth: authPermissions
+            })
+          }
+          let messages = senderConn.processAfterAuth
+          senderConn.processAfterAuth = []
+
+          messages.forEach(m =>
+            this.computeMessage(m[0], m[1], m[2], m[3], m[4])
+          )
+        })
+      }
+    }
+    if ((skipAuth || senderConn.auth != null) && (messageType !== 'update' || senderConn.isSynced)) {
+      this.computeMessage(messageType, senderConn, decoder, encoder, sender, skipAuth)
+    } else {
+      senderConn.processAfterSync.push([messageType, senderConn, decoder, encoder, sender, false])
+    }
+  }
+
+  computeMessage (messageType, senderConn, decoder, encoder, sender, skipAuth) {
+    if (messageType === 'sync step 1' && (senderConn.auth === 'write' || senderConn.auth === 'read')) {
+      // cannot wait for sync step 1 to finish, because we may wait for sync step 2 in sync step 1 (->lock)
+      readSyncStep1(decoder, encoder, this.y, senderConn, sender)
+    } else {
+      const y = this.y
+      y.transact(function () {
+        if (messageType === 'sync step 2' && senderConn.auth === 'write') {
+          readSyncStep2(decoder, encoder, y, senderConn, sender)
+        } else if (messageType === 'update' && (skipAuth || senderConn.auth === 'write')) {
+          integrateRemoteStructs(decoder, encoder, y, senderConn, sender)
+        } else {
+          throw new Error('Unable to receive message')
+        }
+      }, true)
+    }
+  }
+
+  _setSyncedWith (user) {
+    if (user != null) {
+      const userConn = this.connections.get(user)
+      userConn.isSynced = true
+      const messages = userConn.processAfterSync
+      userConn.processAfterSync = []
+      messages.forEach(m => {
+        this.computeMessage(m[0], m[1], m[2], m[3], m[4])
+      })
+    }
+    const conns = Array.from(this.connections.values())
+    if (conns.length > 0 && conns.every(u => u.isSynced)) {
+      this._fireIsSyncedListeners()
+    }
+  }
 }

src/Connectors/Test.js

@@ -1,165 +0,0 @@
-/* global getRandom, async */
-'use strict'
-
-module.exports = function (Y) {
-  var globalRoom = {
-    users: {},
-    buffers: {},
-    removeUser: function (user) {
-      for (var i in this.users) {
-        this.users[i].userLeft(user)
-      }
-      delete this.users[user]
-      delete this.buffers[user]
-    },
-    addUser: function (connector) {
-      this.users[connector.userId] = connector
-      this.buffers[connector.userId] = {}
-      for (var uname in this.users) {
-        if (uname !== connector.userId) {
-          var u = this.users[uname]
-          u.userJoined(connector.userId, 'master')
-          connector.userJoined(u.userId, 'master')
-        }
-      }
-    },
-    whenTransactionsFinished: function () {
-      var ps = []
-      for (var name in this.users) {
-        ps.push(this.users[name].y.db.whenTransactionsFinished())
-      }
-      return Promise.all(ps)
-    },
-    flushOne: function flushOne () {
-      var bufs = []
-      for (var receiver in globalRoom.buffers) {
-        let buff = globalRoom.buffers[receiver]
-        var push = false
-        for (let sender in buff) {
-          if (buff[sender].length > 0) {
-            push = true
-            break
-          }
-        }
-        if (push) {
-          bufs.push(receiver)
-        }
-      }
-      if (bufs.length > 0) {
-        var userId = getRandom(bufs)
-        let buff = globalRoom.buffers[userId]
-        let sender = getRandom(Object.keys(buff))
-        var m = buff[sender].shift()
-        if (buff[sender].length === 0) {
-          delete buff[sender]
-        }
-        var user = globalRoom.users[userId]
-        user.receiveMessage(m[0], m[1])
-        return user.y.db.whenTransactionsFinished()
-      } else {
-        return false
-      }
-    },
-    flushAll: function () {
-      return new Promise(function (resolve) {
-        // flushes may result in more created operations,
-        // flush until there is nothing more to flush
-        function nextFlush () {
-          var c = globalRoom.flushOne()
-          if (c) {
-            while (c) {
-              c = globalRoom.flushOne()
-            }
-            globalRoom.whenTransactionsFinished().then(nextFlush)
-          } else {
-            setTimeout(function () {
-              var c = globalRoom.flushOne()
-              if (c) {
-                c.then(function () {
-                  globalRoom.whenTransactionsFinished().then(nextFlush)
-                })
-              } else {
-                resolve()
-              }
-            }, 0)
-          }
-        }
-        globalRoom.whenTransactionsFinished().then(nextFlush)
-      })
-    }
-  }
-  Y.utils.globalRoom = globalRoom
-
-  var userIdCounter = 0
-
-  class Test extends Y.AbstractConnector {
-    constructor (y, options) {
-      if (options === undefined) {
-        throw new Error('Options must not be undefined!')
-      }
-      options.role = 'master'
-      options.forwardToSyncingClients = false
-      super(y, options)
-      this.setUserId((userIdCounter++) + '').then(() => {
-        globalRoom.addUser(this)
-      })
-      this.globalRoom = globalRoom
-      this.syncingClientDuration = 0
-    }
-    receiveMessage (sender, m) {
-      super.receiveMessage(sender, JSON.parse(JSON.stringify(m)))
-    }
-    send (userId, message) {
-      var buffer = globalRoom.buffers[userId]
-      if (buffer != null) {
-        if (buffer[this.userId] == null) {
-          buffer[this.userId] = []
-        }
-        buffer[this.userId].push(JSON.parse(JSON.stringify([this.userId, message])))
-      }
-    }
-    broadcast (message) {
-      for (var key in globalRoom.buffers) {
-        var buff = globalRoom.buffers[key]
-        if (buff[this.userId] == null) {
-          buff[this.userId] = []
-        }
-        buff[this.userId].push(JSON.parse(JSON.stringify([this.userId, message])))
-      }
-    }
-    isDisconnected () {
-      return globalRoom.users[this.userId] == null
-    }
-    reconnect () {
-      if (this.isDisconnected()) {
-        globalRoom.addUser(this)
-        super.reconnect()
-      }
-      return Y.utils.globalRoom.flushAll()
-    }
-    disconnect () {
-      if (!this.isDisconnected()) {
-        globalRoom.removeUser(this.userId)
-        super.disconnect()
-      }
-      return this.y.db.whenTransactionsFinished()
-    }
-    flush () {
-      var self = this
-      return async(function * () {
-        var buff = globalRoom.buffers[self.userId]
-        while (Object.keys(buff).length > 0) {
-          var sender = getRandom(Object.keys(buff))
-          var m = buff[sender].shift()
-          if (buff[sender].length === 0) {
-            delete buff[sender]
-          }
-          this.receiveMessage(m[0], m[1])
-        }
-        yield self.whenTransactionsFinished()
-      })
-    }
-  }
-
-  Y.Test = Test
-}

src/Database.js

@@ -1,510 +0,0 @@
-/* @flow */
-'use strict'
-
-module.exports = function (Y /* :any */) {
-  /*
-    Partial definition of an OperationStore.
-    TODO: name it Database, operation store only holds operations.
-
-    A database definition must alse define the following methods:
-    * logTable() (optional)
-      - show relevant information information in a table
-    * requestTransaction(makeGen)
-      - request a transaction
-    * destroy()
-      - destroy the database
-  */
-  class AbstractDatabase {
-    /* ::
-    y: YConfig;
-    forwardAppliedOperations: boolean;
-    listenersById: Object;
-    listenersByIdExecuteNow: Array<Object>;
-    listenersByIdRequestPending: boolean;
-    initializedTypes: Object;
-    whenUserIdSetListener: ?Function;
-    waitingTransactions: Array<Transaction>;
-    transactionInProgress: boolean;
-    executeOrder: Array<Object>;
-    gc1: Array<Struct>;
-    gc2: Array<Struct>;
-    gcTimeout: number;
-    gcInterval: any;
-    garbageCollect: Function;
-    executeOrder: Array<any>; // for debugging only
-    userId: UserId;
-    opClock: number;
-    transactionsFinished: ?{promise: Promise, resolve: any};
-    transact: (x: ?Generator) => any;
-    */
-    constructor (y, opts) {
-      this.y = y
-      var os = this
-      this.userId = null
-      var resolve
-      this.userIdPromise = new Promise(function (r) {
-        resolve = r
-      })
-      this.userIdPromise.resolve = resolve
-      // whether to broadcast all applied operations (insert & delete hook)
-      this.forwardAppliedOperations = false
-      // E.g. this.listenersById[id] : Array<Listener>
-      this.listenersById = {}
-      // Execute the next time a transaction is requested
-      this.listenersByIdExecuteNow = []
-      // A transaction is requested
-      this.listenersByIdRequestPending = false
-      /* To make things more clear, the following naming conventions:
-         * ls : we put this.listenersById on ls
-         * l : Array<Listener>
-         * id : Id (can't use as property name)
-         * sid : String (converted from id via JSON.stringify
-                         so we can use it as a property name)
-
-        Always remember to first overwrite
-        a property before you iterate over it!
-      */
-      // TODO: Use ES7 Weak Maps. This way types that are no longer user,
-      // wont be kept in memory.
-      this.initializedTypes = {}
-      this.waitingTransactions = []
-      this.transactionInProgress = false
-      this.transactionIsFlushed = false
-      if (typeof YConcurrency_TestingMode !== 'undefined') {
-        this.executeOrder = []
-      }
-      this.gc1 = [] // first stage
-      this.gc2 = [] // second stage -> after that, remove the op
-      this.gcTimeout = !opts.gcTimeout ? 50000 : opts.gcTimeouts
-      function garbageCollect () {
-        return os.whenTransactionsFinished().then(function () {
-          if (os.gc1.length > 0 || os.gc2.length > 0) {
-            if (!os.y.isConnected()) {
-              console.warn('gc should be empty when disconnected!')
-            }
-            return new Promise((resolve) => {
-              os.requestTransaction(function * () {
-                if (os.y.connector != null && os.y.connector.isSynced) {
-                  for (var i = 0; i < os.gc2.length; i++) {
-                    var oid = os.gc2[i]
-                    yield* this.garbageCollectOperation(oid)
-                  }
-                  os.gc2 = os.gc1
-                  os.gc1 = []
-                }
-                // TODO: Use setInterval here instead (when garbageCollect is called several times there will be several timeouts..)
-                if (os.gcTimeout > 0) {
-                  os.gcInterval = setTimeout(garbageCollect, os.gcTimeout)
-                }
-                resolve()
-              })
-            })
-          } else {
-            // TODO: see above
-            if (os.gcTimeout > 0) {
-              os.gcInterval = setTimeout(garbageCollect, os.gcTimeout)
-            }
-            return Promise.resolve()
-          }
-        })
-      }
-      this.garbageCollect = garbageCollect
-      if (this.gcTimeout > 0) {
-        garbageCollect()
-      }
-    }
-    queueGarbageCollector (id) {
-      if (this.y.isConnected()) {
-        this.gc1.push(id)
-      }
-    }
-    emptyGarbageCollector () {
-      return new Promise(resolve => {
-        var check = () => {
-          if (this.gc1.length > 0 || this.gc2.length > 0) {
-            this.garbageCollect().then(check)
-          } else {
-            resolve()
-          }
-        }
-        setTimeout(check, 0)
-      })
-    }
-    addToDebug () {
-      if (typeof YConcurrency_TestingMode !== 'undefined') {
-        var command /* :string */ = Array.prototype.map.call(arguments, function (s) {
-          if (typeof s === 'string') {
-            return s
-          } else {
-            return JSON.stringify(s)
-          }
-        }).join('').replace(/"/g, "'").replace(/,/g, ', ').replace(/:/g, ': ')
-        this.executeOrder.push(command)
-      }
-    }
-    getDebugData () {
-      console.log(this.executeOrder.join('\n'))
-    }
-    stopGarbageCollector () {
-      var self = this
-      return new Promise(function (resolve) {
-        self.requestTransaction(function * () {
-          var ungc /* :Array<Struct> */ = self.gc1.concat(self.gc2)
-          self.gc1 = []
-          self.gc2 = []
-          for (var i = 0; i < ungc.length; i++) {
-            var op = yield* this.getOperation(ungc[i])
-            if (op != null) {
-              delete op.gc
-              yield* this.setOperation(op)
-            }
-          }
-          resolve()
-        })
-      })
-    }
-    /*
-      Try to add to GC.
-
-      TODO: rename this function
-
-      Rulez:
-      * Only gc if this user is online
-      * The most left element in a list must not be gc'd.
-        => There is at least one element in the list
-
-      returns true iff op was added to GC
-    */
-    * addToGarbageCollector (op, left) {
-      if (
-        op.gc == null &&
-        op.deleted === true
-      ) {
-        var gc = false
-        if (left != null && left.deleted === true) {
-          gc = true
-        } else if (op.content != null && op.content.length > 1) {
-          op = yield* this.getInsertionCleanStart([op.id[0], op.id[1] + 1])
-          gc = true
-        }
-        if (gc) {
-          op.gc = true
-          yield* this.setOperation(op)
-          this.store.queueGarbageCollector(op.id)
-          return true
-        }
-      }
-      return false
-    }
-    removeFromGarbageCollector (op) {
-      function filter (o) {
-        return !Y.utils.compareIds(o, op.id)
-      }
-      this.gc1 = this.gc1.filter(filter)
-      this.gc2 = this.gc2.filter(filter)
-      delete op.gc
-    }
-    * destroy () {
-      clearInterval(this.gcInterval)
-      this.gcInterval = null
-      for (var key in this.initializedTypes) {
-        var type = this.initializedTypes[key]
-        if (type._destroy != null) {
-          type._destroy()
-        } else {
-          console.error('The type you included does not provide destroy functionality, it will remain in memory (updating your packages will help).')
-        }
-      }
-    }
-    setUserId (userId) {
-      if (!this.userIdPromise.inProgress) {
-        this.userIdPromise.inProgress = true
-        var self = this
-        self.requestTransaction(function * () {
-          self.userId = userId
-          var state = yield* this.getState(userId)
-          self.opClock = state.clock
-          self.userIdPromise.resolve(userId)
-        })
-      }
-      return this.userIdPromise
-    }
-    whenUserIdSet (f) {
-      this.userIdPromise.then(f)
-    }
-    getNextOpId (numberOfIds) {
-      if (numberOfIds == null) {
-        throw new Error('getNextOpId expects the number of created ids to create!')
-      } else if (this.userId == null) {
-        throw new Error('OperationStore not yet initialized!')
-      } else {
-        var id = [this.userId, this.opClock]
-        this.opClock += numberOfIds
-        return id
-      }
-    }
-    /*
-      Apply a list of operations.
-
-      * get a transaction
-      * check whether all Struct.*.requiredOps are in the OS
-      * check if it is an expected op (otherwise wait for it)
-      * check if was deleted, apply a delete operation after op was applied
-    */
-    apply (ops) {
-      for (var i = 0; i < ops.length; i++) {
-        var o = ops[i]
-        if (o.id == null || o.id[0] !== this.y.connector.userId) {
-          var required = Y.Struct[o.struct].requiredOps(o)
-          if (o.requires != null) {
-            required = required.concat(o.requires)
-          }
-          this.whenOperationsExist(required, o)
-        }
-      }
-    }
-    /*
-      op is executed as soon as every operation requested is available.
-      Note that Transaction can (and should) buffer requests.
-    */
-    whenOperationsExist (ids, op) {
-      if (ids.length > 0) {
-        let listener = {
-          op: op,
-          missing: ids.length
-        }
-
-        for (let i = 0; i < ids.length; i++) {
-          let id = ids[i]
-          let sid = JSON.stringify(id)
-          let l = this.listenersById[sid]
-          if (l == null) {
-            l = []
-            this.listenersById[sid] = l
-          }
-          l.push(listener)
-        }
-      } else {
-        this.listenersByIdExecuteNow.push({
-          op: op
-        })
-      }
-
-      if (this.listenersByIdRequestPending) {
-        return
-      }
-
-      this.listenersByIdRequestPending = true
-      var store = this
-
-      this.requestTransaction(function * () {
-        var exeNow = store.listenersByIdExecuteNow
-        store.listenersByIdExecuteNow = []
-
-        var ls = store.listenersById
-        store.listenersById = {}
-
-        store.listenersByIdRequestPending = false
-
-        for (let key = 0; key < exeNow.length; key++) {
-          let o = exeNow[key].op
-          yield* store.tryExecute.call(this, o)
-        }
-
-        for (var sid in ls) {
-          var l = ls[sid]
-          var id = JSON.parse(sid)
-          var op
-          if (typeof id[1] === 'string') {
-            op = yield* this.getOperation(id)
-          } else {
-            op = yield* this.getInsertion(id)
-          }
-          if (op == null) {
-            store.listenersById[sid] = l
-          } else {
-            for (let i = 0; i < l.length; i++) {
-              let listener = l[i]
-              let o = listener.op
-              if (--listener.missing === 0) {
-                yield* store.tryExecute.call(this, o)
-              }
-            }
-          }
-        }
-      })
-    }
-    /*
-      Actually execute an operation, when all expected operations are available.
-    */
-    /* :: // TODO: this belongs somehow to transaction
-    store: Object;
-    getOperation: any;
-    isGarbageCollected: any;
-    addOperation: any;
-    whenOperationsExist: any;
-    */
-    * tryExecute (op) {
-      this.store.addToDebug('yield* this.store.tryExecute.call(this, ', JSON.stringify(op), ')')
-      if (op.struct === 'Delete') {
-        yield* Y.Struct.Delete.execute.call(this, op)
-        // this is now called in Transaction.deleteOperation!
-        // yield* this.store.operationAdded(this, op)
-      } else {
-        // check if this op was defined
-        var defined = yield* this.getInsertion(op.id)
-        while (defined != null && defined.content != null) {
-          // check if this op has a longer content in the case it is defined
-          if (defined.id[1] + defined.content.length < op.id[1] + op.content.length) {
-            var overlapSize = defined.content.length - (op.id[1] - defined.id[1])
-            op.content.splice(0, overlapSize)
-            op.id = [op.id[0], op.id[1] + overlapSize]
-            op.left = Y.utils.getLastId(defined)
-            op.origin = op.left
-            defined = yield* this.getOperation(op.id) // getOperation suffices here
-          } else {
-            break
-          }
-        }
-        if (defined == null) {
-          var opid = op.id
-          var isGarbageCollected = yield* this.isGarbageCollected(opid)
-          if (!isGarbageCollected) {
-            // TODO: reduce number of get / put calls for op ..
-            yield* Y.Struct[op.struct].execute.call(this, op)
-            yield* this.addOperation(op)
-            yield* this.store.operationAdded(this, op)
-            // operationAdded can change op..
-            op = yield* this.getOperation(opid)
-            // if insertion, try to combine with left
-            yield* this.tryCombineWithLeft(op)
-          }
-        }
-      }
-    }
-    /*
-     * Called by a transaction when an operation is added.
-     * This function is especially important for y-indexeddb, where several instances may share a single database.
-     * Every time an operation is created by one instance, it is send to all other instances and operationAdded is called
-     *
-     * If it's not a Delete operation:
-     *   * Checks if another operation is executable (listenersById)
-     *   * Update state, if possible
-     *
-     * Always:
-     *   * Call type
-     */
-    * operationAdded (transaction, op) {
-      if (op.struct === 'Delete') {
-        var target = yield* transaction.getInsertion(op.target)
-        var type = this.initializedTypes[JSON.stringify(target.parent)]
-        if (type != null) {
-          yield* type._changed(transaction, op)
-        }
-      } else {
-        // increase SS
-        yield* transaction.updateState(op.id[0])
-        var opLen = op.content != null ? op.content.length : 1
-        for (let i = 0; i < opLen; i++) {
-          // notify whenOperation listeners (by id)
-          var sid = JSON.stringify([op.id[0], op.id[1] + i])
-          var l = this.listenersById[sid]
-          delete this.listenersById[sid]
-          if (l != null) {
-            for (var key in l) {
-              var listener = l[key]
-              if (--listener.missing === 0) {
-                this.whenOperationsExist([], listener.op)
-              }
-            }
-          }
-        }
-        var t = this.initializedTypes[JSON.stringify(op.parent)]
-
-        // if parent is deleted, mark as gc'd and return
-        if (op.parent != null) {
-          var parentIsDeleted = yield* transaction.isDeleted(op.parent)
-          if (parentIsDeleted) {
-            yield* transaction.deleteList(op.id)
-            return
-          }
-        }
-
-        // notify parent, if it was instanciated as a custom type
-        if (t != null) {
-          let o = Y.utils.copyOperation(op)
-          yield* t._changed(transaction, o)
-        }
-        if (!op.deleted) {
-          // Delete if DS says this is actually deleted
-          var len = op.content != null ? op.content.length : 1
-          var startId = op.id // You must not use op.id in the following loop, because op will change when deleted
-            // TODO: !! console.log('TODO: change this before commiting')
-          for (let i = 0; i < len; i++) {
-            var id = [startId[0], startId[1] + i]
-            var opIsDeleted = yield* transaction.isDeleted(id)
-            if (opIsDeleted) {
-              var delop = {
-                struct: 'Delete',
-                target: id
-              }
-              yield* this.tryExecute.call(transaction, delop)
-            }
-          }
-        }
-      }
-    }
-    whenTransactionsFinished () {
-      if (this.transactionInProgress) {
-        if (this.transactionsFinished == null) {
-          var resolve
-          var promise = new Promise(function (r) {
-            resolve = r
-          })
-          this.transactionsFinished = {
-            resolve: resolve,
-            promise: promise
-          }
-          return promise
-        } else {
-          return this.transactionsFinished.promise
-        }
-      } else {
-        return Promise.resolve()
-      }
-    }
-    // Check if there is another transaction request.
-    // * the last transaction is always a flush :)
-    getNextRequest () {
-      if (this.waitingTransactions.length === 0) {
-        if (this.transactionIsFlushed) {
-          this.transactionInProgress = false
-          this.transactionIsFlushed = false
-          if (this.transactionsFinished != null) {
-            this.transactionsFinished.resolve()
-            this.transactionsFinished = null
-          }
-          return null
-        } else {
-          this.transactionIsFlushed = true
-          return function * () {
-            yield* this.flush()
-          }
-        }
-      } else {
-        this.transactionIsFlushed = false
-        return this.waitingTransactions.shift()
-      }
-    }
-    requestTransaction (makeGen/* :any */, callImmediately) {
-      this.waitingTransactions.push(makeGen)
-      if (!this.transactionInProgress) {
-        this.transactionInProgress = true
-        setTimeout(() => {
-          this.transact(this.getNextRequest())
-        }, 0)
-      }
-    }
-  }
-  Y.AbstractDatabase = AbstractDatabase
-}

src/Database.spec.js

@@ -1,354 +0,0 @@
-/* global async, databases, describe, beforeEach, afterEach */
-/* eslint-env browser,jasmine,console */
-'use strict'
-
-var Y = require('./SpecHelper.js')
-
-for (let database of databases) {
-  describe(`Database (${database})`, function () {
-    var store
-    describe('DeleteStore', function () {
-      describe('Basic', function () {
-        beforeEach(function () {
-          store = new Y[database](null, {
-            gcTimeout: -1,
-            namespace: 'testing'
-          })
-        })
-        afterEach(function (done) {
-          store.requestTransaction(function * () {
-            yield* this.store.destroy()
-            done()
-          })
-        })
-        it('Deleted operation is deleted', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['u1', 10], 1)
-            expect(yield* this.isDeleted(['u1', 10])).toBeTruthy()
-            expect(yield* this.getDeleteSet()).toEqual({'u1': [[10, 1, false]]})
-            done()
-          })
-        }))
-        it('Deleted operation extends other deleted operation', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['u1', 10], 1)
-            yield* this.markDeleted(['u1', 11], 1)
-            expect(yield* this.isDeleted(['u1', 10])).toBeTruthy()
-            expect(yield* this.isDeleted(['u1', 11])).toBeTruthy()
-            expect(yield* this.getDeleteSet()).toEqual({'u1': [[10, 2, false]]})
-            done()
-          })
-        }))
-        it('Deleted operation extends other deleted operation', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['0', 3], 1)
-            yield* this.markDeleted(['0', 4], 1)
-            yield* this.markDeleted(['0', 2], 1)
-            expect(yield* this.getDeleteSet()).toEqual({'0': [[2, 3, false]]})
-            done()
-          })
-        }))
-        it('Debug #1', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['166', 0], 1)
-            yield* this.markDeleted(['166', 2], 1)
-            yield* this.markDeleted(['166', 0], 1)
-            yield* this.markDeleted(['166', 2], 1)
-            yield* this.markGarbageCollected(['166', 2], 1)
-            yield* this.markDeleted(['166', 1], 1)
-            yield* this.markDeleted(['166', 3], 1)
-            yield* this.markGarbageCollected(['166', 3], 1)
-            yield* this.markDeleted(['166', 0], 1)
-            expect(yield* this.getDeleteSet()).toEqual({'166': [[0, 2, false], [2, 2, true]]})
-            done()
-          })
-        }))
-        it('Debug #2', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['293', 0], 1)
-            yield* this.markDeleted(['291', 2], 1)
-            yield* this.markDeleted(['291', 2], 1)
-            yield* this.markGarbageCollected(['293', 0], 1)
-            yield* this.markDeleted(['293', 1], 1)
-            yield* this.markGarbageCollected(['291', 2], 1)
-            expect(yield* this.getDeleteSet()).toEqual({'291': [[2, 1, true]], '293': [[0, 1, true], [1, 1, false]]})
-            done()
-          })
-        }))
-        it('Debug #3', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['581', 0], 1)
-            yield* this.markDeleted(['581', 1], 1)
-            yield* this.markDeleted(['580', 0], 1)
-            yield* this.markDeleted(['580', 0], 1)
-            yield* this.markGarbageCollected(['581', 0], 1)
-            yield* this.markDeleted(['581', 2], 1)
-            yield* this.markDeleted(['580', 1], 1)
-            yield* this.markDeleted(['580', 2], 1)
-            yield* this.markDeleted(['580', 1], 1)
-            yield* this.markDeleted(['580', 2], 1)
-            yield* this.markGarbageCollected(['581', 2], 1)
-            yield* this.markGarbageCollected(['581', 1], 1)
-            yield* this.markGarbageCollected(['580', 1], 1)
-            expect(yield* this.getDeleteSet()).toEqual({'580': [[0, 1, false], [1, 1, true], [2, 1, false]], '581': [[0, 3, true]]})
-            done()
-          })
-        }))
-        it('Debug #4', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['544', 0], 1)
-            yield* this.markDeleted(['543', 2], 1)
-            yield* this.markDeleted(['544', 0], 1)
-            yield* this.markDeleted(['543', 2], 1)
-            yield* this.markGarbageCollected(['544', 0], 1)
-            yield* this.markDeleted(['545', 1], 1)
-            yield* this.markDeleted(['543', 4], 1)
-            yield* this.markDeleted(['543', 3], 1)
-            yield* this.markDeleted(['544', 1], 1)
-            yield* this.markDeleted(['544', 2], 1)
-            yield* this.markDeleted(['544', 1], 1)
-            yield* this.markDeleted(['544', 2], 1)
-            yield* this.markGarbageCollected(['543', 2], 1)
-            yield* this.markGarbageCollected(['543', 4], 1)
-            yield* this.markGarbageCollected(['544', 2], 1)
-            yield* this.markGarbageCollected(['543', 3], 1)
-            expect(yield* this.getDeleteSet()).toEqual({'543': [[2, 3, true]], '544': [[0, 1, true], [1, 1, false], [2, 1, true]], '545': [[1, 1, false]]})
-            done()
-          })
-        }))
-        it('Debug #5', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.applyDeleteSet({'16': [[1, 2, false]], '17': [[0, 1, true], [1, 3, false]]})
-            expect(yield* this.getDeleteSet()).toEqual({'16': [[1, 2, false]], '17': [[0, 1, true], [1, 3, false]]})
-            yield* this.applyDeleteSet({'16': [[1, 2, false]], '17': [[0, 4, true]]})
-            expect(yield* this.getDeleteSet()).toEqual({'16': [[1, 2, false]], '17': [[0, 4, true]]})
-            done()
-          })
-        }))
-        it('Debug #6', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.applyDeleteSet({'40': [[0, 3, false]]})
-            expect(yield* this.getDeleteSet()).toEqual({'40': [[0, 3, false]]})
-            yield* this.applyDeleteSet({'39': [[2, 2, false]], '40': [[0, 1, true], [1, 2, false]], '41': [[2, 1, false]]})
-            expect(yield* this.getDeleteSet()).toEqual({'39': [[2, 2, false]], '40': [[0, 1, true], [1, 2, false]], '41': [[2, 1, false]]})
-            done()
-          })
-        }))
-        it('Debug #7', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield* this.markDeleted(['9', 2], 1)
-            yield* this.markDeleted(['11', 2], 1)
-            yield* this.markDeleted(['11', 4], 1)
-            yield* this.markDeleted(['11', 1], 1)
-            yield* this.markDeleted(['9', 4], 1)
-            yield* this.markDeleted(['10', 0], 1)
-            yield* this.markGarbageCollected(['11', 2], 1)
-            yield* this.markDeleted(['11', 2], 1)
-            yield* this.markGarbageCollected(['11', 3], 1)
-            yield* this.markDeleted(['11', 3], 1)
-            yield* this.markDeleted(['11', 3], 1)
-            yield* this.markDeleted(['9', 4], 1)
-            yield* this.markDeleted(['10', 0], 1)
-            yield* this.markGarbageCollected(['11', 1], 1)
-            yield* this.markDeleted(['11', 1], 1)
-            expect(yield* this.getDeleteSet()).toEqual({'9': [[2, 1, false], [4, 1, false]], '10': [[0, 1, false]], '11': [[1, 3, true], [4, 1, false]]})
-            done()
-          })
-        }))
-      })
-    })
-    describe('OperationStore', function () {
-      describe('Basic Tests', function () {
-        beforeEach(function () {
-          store = new Y[database](null, {
-            gcTimeout: -1,
-            namespace: 'testing'
-          })
-        })
-        afterEach(function (done) {
-          store.requestTransaction(function * () {
-            yield* this.store.destroy()
-            done()
-          })
-        })
-        it('debug #1', function (done) {
-          store.requestTransaction(function * () {
-            yield* this.os.put({id: [2]})
-            yield* this.os.put({id: [0]})
-            yield* this.os.delete([2])
-            yield* this.os.put({id: [1]})
-            expect(yield* this.os.find([0])).toBeTruthy()
-            expect(yield* this.os.find([1])).toBeTruthy()
-            expect(yield* this.os.find([2])).toBeFalsy()
-            done()
-          })
-        })
-        it('can add&retrieve 5 elements', function (done) {
-          store.requestTransaction(function * () {
-            yield* this.os.put({val: 'four', id: [4]})
-            yield* this.os.put({val: 'one', id: [1]})
-            yield* this.os.put({val: 'three', id: [3]})
-            yield* this.os.put({val: 'two', id: [2]})
-            yield* this.os.put({val: 'five', id: [5]})
-            expect((yield* this.os.find([1])).val).toEqual('one')
-            expect((yield* this.os.find([2])).val).toEqual('two')
-            expect((yield* this.os.find([3])).val).toEqual('three')
-            expect((yield* this.os.find([4])).val).toEqual('four')
-            expect((yield* this.os.find([5])).val).toEqual('five')
-            done()
-          })
-        })
-        it('5 elements do not exist anymore after deleting them', function (done) {
-          store.requestTransaction(function * () {
-            yield* this.os.put({val: 'four', id: [4]})
-            yield* this.os.put({val: 'one', id: [1]})
-            yield* this.os.put({val: 'three', id: [3]})
-            yield* this.os.put({val: 'two', id: [2]})
-            yield* this.os.put({val: 'five', id: [5]})
-            yield* this.os.delete([4])
-            expect(yield* this.os.find([4])).not.toBeTruthy()
-            yield* this.os.delete([3])
-            expect(yield* this.os.find([3])).not.toBeTruthy()
-            yield* this.os.delete([2])
-            expect(yield* this.os.find([2])).not.toBeTruthy()
-            yield* this.os.delete([1])
-            expect(yield* this.os.find([1])).not.toBeTruthy()
-            yield* this.os.delete([5])
-            expect(yield* this.os.find([5])).not.toBeTruthy()
-            done()
-          })
-        })
-      })
-      var numberOfOSTests = 1000
-      describe(`Random Tests - after adding&deleting (0.8/0.2) ${numberOfOSTests} times`, function () {
-        var elements = []
-        beforeAll(function (done) {
-          store = new Y[database](null, {
-            gcTimeout: -1,
-            namespace: 'testing'
-          })
-          store.requestTransaction(function * () {
-            for (var i = 0; i < numberOfOSTests; i++) {
-              var r = Math.random()
-              if (r < 0.8) {
-                var obj = [Math.floor(Math.random() * numberOfOSTests * 10000)]
-                if (!(yield* this.os.find(obj))) {
-                  elements.push(obj)
-                  yield* this.os.put({id: obj})
-                }
-              } else if (elements.length > 0) {
-                var elemid = Math.floor(Math.random() * elements.length)
-                var elem = elements[elemid]
-                elements = elements.filter(function (e) {
-                  return !Y.utils.compareIds(e, elem)
-                })
-                yield* this.os.delete(elem)
-              }
-            }
-            done()
-          })
-        })
-        afterAll(function (done) {
-          store.requestTransaction(function * () {
-            yield* this.store.destroy()
-            done()
-          })
-        })
-        it('can find every object', function (done) {
-          store.requestTransaction(function * () {
-            for (var id of elements) {
-              expect((yield* this.os.find(id)).id).toEqual(id)
-            }
-            done()
-          })
-        })
-
-        it('can find every object with lower bound search', function (done) {
-          store.requestTransaction(function * () {
-            for (var id of elements) {
-              var e = yield* this.os.findWithLowerBound(id)
-              expect(e.id).toEqual(id)
-            }
-            done()
-          })
-        })
-
-        it('iterating over a tree with lower bound yields the right amount of results', function (done) {
-          var lowerBound = elements[Math.floor(Math.random() * elements.length)]
-          var expectedResults = elements.filter(function (e, pos) {
-            return (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) && elements.indexOf(e) === pos
-          }).length
-
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield* this.os.iterate(this, lowerBound, null, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-
-        it('iterating over a tree without bounds yield the right amount of results', function (done) {
-          var lowerBound = null
-          var expectedResults = elements.filter(function (e, pos) {
-            return elements.indexOf(e) === pos
-          }).length
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield* this.os.iterate(this, lowerBound, null, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-
-        it('iterating over a tree with upper bound yields the right amount of results', function (done) {
-          var upperBound = elements[Math.floor(Math.random() * elements.length)]
-          var expectedResults = elements.filter(function (e, pos) {
-            return (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) && elements.indexOf(e) === pos
-          }).length
-
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield* this.os.iterate(this, null, upperBound, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-
-        it('iterating over a tree with upper and lower bounds yield the right amount of results', function (done) {
-          var b1 = elements[Math.floor(Math.random() * elements.length)]
-          var b2 = elements[Math.floor(Math.random() * elements.length)]
-          var upperBound, lowerBound
-          if (Y.utils.smaller(b1, b2)) {
-            lowerBound = b1
-            upperBound = b2
-          } else {
-            lowerBound = b2
-            upperBound = b1
-          }
-          var expectedResults = elements.filter(function (e, pos) {
-            return (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) &&
-              (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) && elements.indexOf(e) === pos
-          }).length
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield* this.os.iterate(this, lowerBound, upperBound, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-      })
-    })
-  })
-}

src/MessageHandler/deleteSet.js

@@ -0,0 +1,130 @@
+import { deleteItemRange } from '../Struct/Delete.js'
+import ID from '../Util/ID.js'
+
+export function stringifyDeleteSet (y, decoder, strBuilder) {
+  let dsLength = decoder.readUint32()
+  for (let i = 0; i < dsLength; i++) {
+    let user = decoder.readVarUint()
+    strBuilder.push(' -' + user + ':')
+    let dvLength = decoder.readVarUint()
+    for (let j = 0; j < dvLength; j++) {
+      let from = decoder.readVarUint()
+      let len = decoder.readVarUint()
+      let gc = decoder.readUint8() === 1
+      strBuilder.push(`clock: ${from}, length: ${len}, gc: ${gc}`)
+    }
+  }
+  return strBuilder
+}
+
+export function writeDeleteSet (y, encoder) {
+  let currentUser = null
+  let currentLength
+  let lastLenPos
+
+  let numberOfUsers = 0
+  let laterDSLenPus = encoder.pos
+  encoder.writeUint32(0)
+
+  y.ds.iterate(null, null, function (n) {
+    var user = n._id.user
+    var clock = n._id.clock
+    var len = n.len
+    var gc = n.gc
+    if (currentUser !== user) {
+      numberOfUsers++
+      // a new user was found
+      if (currentUser !== null) { // happens on first iteration
+        encoder.setUint32(lastLenPos, currentLength)
+      }
+      currentUser = user
+      encoder.writeVarUint(user)
+      // pseudo-fill pos
+      lastLenPos = encoder.pos
+      encoder.writeUint32(0)
+      currentLength = 0
+    }
+    encoder.writeVarUint(clock)
+    encoder.writeVarUint(len)
+    encoder.writeUint8(gc ? 1 : 0)
+    currentLength++
+  })
+  if (currentUser !== null) { // happens on first iteration
+    encoder.setUint32(lastLenPos, currentLength)
+  }
+  encoder.setUint32(laterDSLenPus, numberOfUsers)
+}
+
+export function readDeleteSet (y, decoder) {
+  let dsLength = decoder.readUint32()
+  for (let i = 0; i < dsLength; i++) {
+    let user = decoder.readVarUint()
+    let dv = []
+    let dvLength = decoder.readUint32()
+    for (let j = 0; j < dvLength; j++) {
+      let from = decoder.readVarUint()
+      let len = decoder.readVarUint()
+      let gc = decoder.readUint8() === 1
+      dv.push([from, len, gc])
+    }
+    if (dvLength > 0) {
+      let pos = 0
+      let d = dv[pos]
+      let deletions = []
+      y.ds.iterate(new ID(user, 0), new ID(user, Number.MAX_VALUE), function (n) {
+        // cases:
+        // 1. d deletes something to the right of n
+        //  => go to next n (break)
+        // 2. d deletes something to the left of n
+        //  => create deletions
+        //  => reset d accordingly
+        //  *)=> if d doesn't delete anything anymore, go to next d (continue)
+        // 3. not 2) and d deletes something that also n deletes
+        //  => reset d so that it doesn't contain n's deletion
+        //  *)=> if d does not delete anything anymore, go to next d (continue)
+        while (d != null) {
+          var diff = 0 // describe the diff of length in 1) and 2)
+          if (n._id.clock + n.len <= d[0]) {
+            // 1)
+            break
+          } else if (d[0] < n._id.clock) {
+            // 2)
+            // delete maximum the len of d
+            // else delete as much as possible
+            diff = Math.min(n._id.clock - d[0], d[1])
+            // deleteItemRange(y, user, d[0], diff)
+            deletions.push([user, d[0], diff])
+          } else {
+            // 3)
+            diff = n._id.clock + n.len - d[0] // never null (see 1)
+            if (d[2] && !n.gc) {
+              // d marks as gc'd but n does not
+              // then delete either way
+              // deleteItemRange(y, user, d[0], Math.min(diff, d[1]))
+              deletions.push([user, d[0], Math.min(diff, d[1])])
+            }
+          }
+          if (d[1] <= diff) {
+            // d doesn't delete anything anymore
+            d = dv[++pos]
+          } else {
+            d[0] = d[0] + diff // reset pos
+            d[1] = d[1] - diff // reset length
+          }
+        }
+      })
+      // TODO: It would be more performant to apply the deletes in the above loop
+      // Adapt the Tree implementation to support delete while iterating
+      for (let i = deletions.length - 1; i >= 0; i--) {
+        const del = deletions[i]
+        deleteItemRange(y, del[0], del[1], del[2])
+      }
+      // for the rest.. just apply it
+      for (; pos < dv.length; pos++) {
+        d = dv[pos]
+        deleteItemRange(y, user, d[0], d[1])
+        // deletions.push([user, d[0], d[1], d[2]])
+      }
+    }
+  }
+}

src/MessageHandler/integrateRemoteStructs.js

@@ -0,0 +1,100 @@
+import { getStruct } from '../Util/structReferences.js'
+import BinaryDecoder from '../Binary/Decoder.js'
+import { logID } from './messageToString.js'
+
+class MissingEntry {
+  constructor (decoder, missing, struct) {
+    this.decoder = decoder
+    this.missing = missing.length
+    this.struct = struct
+  }
+}
+
+/**
+ * Integrate remote struct
+ * When a remote struct is integrated, other structs might be ready to ready to
+ * integrate.
+ */
+function _integrateRemoteStructHelper (y, struct) {
+  const id = struct._id
+  if (id === undefined) {
+    struct._integrate(y)
+  } else {
+    if (y.ss.getState(id.user) > id.clock) {
+      return
+    }
+    struct._integrate(y)
+    let msu = y._missingStructs.get(id.user)
+    if (msu != null) {
+      let clock = id.clock
+      const finalClock = clock + struct._length
+      for (;clock < finalClock; clock++) {
+        const missingStructs = msu.get(clock)
+        if (missingStructs !== undefined) {
+          missingStructs.forEach(missingDef => {
+            missingDef.missing--
+            if (missingDef.missing === 0) {
+              const decoder = missingDef.decoder
+              let oldPos = decoder.pos
+              let missing = missingDef.struct._fromBinary(y, decoder)
+              decoder.pos = oldPos
+              if (missing.length === 0) {
+                y._readyToIntegrate.push(missingDef.struct)
+              }
+            }
+          })
+          msu.delete(clock)
+        }
+      }
+    }
+  }
+}
+
+export function stringifyStructs (y, decoder, strBuilder) {
+  const len = decoder.readUint32()
+  for (let i = 0; i < len; i++) {
+    let reference = decoder.readVarUint()
+    let Constr = getStruct(reference)
+    let struct = new Constr()
+    let missing = struct._fromBinary(y, decoder)
+    let logMessage = '  ' + struct._logString()
+    if (missing.length > 0) {
+      logMessage += ' .. missing: ' + missing.map(logID).join(', ')
+    }
+    strBuilder.push(logMessage)
+  }
+}
+
+export function integrateRemoteStructs (decoder, encoder, y) {
+  const len = decoder.readUint32()
+  for (let i = 0; i < len; i++) {
+    let reference = decoder.readVarUint()
+    let Constr = getStruct(reference)
+    let struct = new Constr()
+    let decoderPos = decoder.pos
+    let missing = struct._fromBinary(y, decoder)
+    if (missing.length === 0) {
+      while (struct != null) {
+        _integrateRemoteStructHelper(y, struct)
+        struct = y._readyToIntegrate.shift()
+      }
+    } else {
+      let _decoder = new BinaryDecoder(decoder.uint8arr)
+      _decoder.pos = decoderPos
+      let missingEntry = new MissingEntry(_decoder, missing, struct)
+      let missingStructs = y._missingStructs
+      for (let i = missing.length - 1; i >= 0; i--) {
+        let m = missing[i]
+        if (!missingStructs.has(m.user)) {
+          missingStructs.set(m.user, new Map())
+        }
+        let msu = missingStructs.get(m.user)
+        if (!msu.has(m.clock)) {
+          msu.set(m.clock, [])
+        }
+        let mArray = msu = msu.get(m.clock)
+        mArray.push(missingEntry)
+      }
+    }
+  }
+}

src/MessageHandler/messageToString.js

@@ -0,0 +1,48 @@
+import BinaryDecoder from '../Binary/Decoder.js'
+import { stringifyStructs } from './integrateRemoteStructs.js'
+import { stringifySyncStep1 } from './syncStep1.js'
+import { stringifySyncStep2 } from './syncStep2.js'
+import ID from '../Util/ID.js'
+import RootID from '../Util/RootID.js'
+import Y from '../Y.js'
+
+export function messageToString ([y, buffer]) {
+  let decoder = new BinaryDecoder(buffer)
+  decoder.readVarString() // read roomname
+  let type = decoder.readVarString()
+  let strBuilder = []
+  strBuilder.push('\n === ' + type + ' ===')
+  if (type === 'update') {
+    stringifyStructs(y, decoder, strBuilder)
+  } else if (type === 'sync step 1') {
+    stringifySyncStep1(y, decoder, strBuilder)
+  } else if (type === 'sync step 2') {
+    stringifySyncStep2(y, decoder, strBuilder)
+  } else {
+    strBuilder.push('-- Unknown message type - probably an encoding issue!!!')
+  }
+  return strBuilder.join('\n')
+}
+
+export function messageToRoomname (buffer) {
+  let decoder = new BinaryDecoder(buffer)
+  decoder.readVarString() // roomname
+  return decoder.readVarString() // messageType
+}
+
+export function logID (id) {
+  if (id !== null && id._id != null) {
+    id = id._id
+  }
+  if (id === null) {
+    return '()'
+  } else if (id instanceof ID) {
+    return `(${id.user},${id.clock})`
+  } else if (id instanceof RootID) {
+    return `(${id.name},${id.type})`
+  } else if (id.constructor === Y) {
+    return `y`
+  } else {
+    throw new Error('This is not a valid ID!')
+  }
+}

src/MessageHandler/stateSet.js

@@ -0,0 +1,23 @@
+
+export function readStateSet (decoder) {
+  let ss = new Map()
+  let ssLength = decoder.readUint32()
+  for (let i = 0; i < ssLength; i++) {
+    let user = decoder.readVarUint()
+    let clock = decoder.readVarUint()
+    ss.set(user, clock)
+  }
+  return ss
+}
+
+export function writeStateSet (y, encoder) {
+  let lenPosition = encoder.pos
+  let len = 0
+  encoder.writeUint32(0)
+  for (let [user, clock] of y.ss.state) {
+    encoder.writeVarUint(user)
+    encoder.writeVarUint(clock)
+    len++
+  }
+  encoder.setUint32(lenPosition, len)
+}

src/MessageHandler/syncStep1.js

@@ -0,0 +1,70 @@
+import BinaryEncoder from '../Binary/Encoder.js'
+import { readStateSet, writeStateSet } from './stateSet.js'
+import { writeDeleteSet } from './deleteSet.js'
+import ID from '../Util/ID.js'
+import { RootFakeUserID } from '../Util/RootID.js'
+
+export function stringifySyncStep1 (y, decoder, strBuilder) {
+  let auth = decoder.readVarString()
+  let protocolVersion = decoder.readVarUint()
+  strBuilder.push(`  - auth: "${auth}"`)
+  strBuilder.push(`  - protocolVersion: ${protocolVersion}`)
+  // write SS
+  let ssBuilder = []
+  let len = decoder.readUint32()
+  for (let i = 0; i < len; i++) {
+    let user = decoder.readVarUint()
+    let clock = decoder.readVarUint()
+    ssBuilder.push(`(${user}:${clock})`)
+  }
+  strBuilder.push('  == SS: ' + ssBuilder.join(','))
+}
+
+export function sendSyncStep1 (connector, syncUser) {
+  let encoder = new BinaryEncoder()
+  encoder.writeVarString(connector.y.room)
+  encoder.writeVarString('sync step 1')
+  encoder.writeVarString(connector.authInfo || '')
+  encoder.writeVarUint(connector.protocolVersion)
+  writeStateSet(connector.y, encoder)
+  connector.send(syncUser, encoder.createBuffer())
+}
+
+export default function writeStructs (encoder, decoder, y, ss) {
+  const lenPos = encoder.pos
+  encoder.writeUint32(0)
+  let len = 0
+  for (let user of y.ss.state.keys()) {
+    let clock = ss.get(user) || 0
+    if (user !== RootFakeUserID) {
+      y.os.iterate(new ID(user, clock), new ID(user, Number.MAX_VALUE), function (struct) {
+        struct._toBinary(encoder)
+        len++
+      })
+    }
+  }
+  encoder.setUint32(lenPos, len)
+}
+
+export function readSyncStep1 (decoder, encoder, y, senderConn, sender) {
+  let protocolVersion = decoder.readVarUint()
+  // check protocol version
+  if (protocolVersion !== y.connector.protocolVersion) {
+    console.warn(
+      `You tried to sync with a Yjs instance that has a different protocol version
+      (You: ${protocolVersion}, Client: ${protocolVersion}).
+      `)
+    y.destroy()
+  }
+  // write sync step 2
+  encoder.writeVarString('sync step 2')
+  encoder.writeVarString(y.connector.authInfo || '')
+  const ss = readStateSet(decoder)
+  writeStructs(encoder, decoder, y, ss)
+  writeDeleteSet(y, encoder)
+  y.connector.send(senderConn.uid, encoder.createBuffer())
+  senderConn.receivedSyncStep2 = true
+  if (y.connector.role === 'slave') {
+    sendSyncStep1(y.connector, sender)
+  }
+}

src/MessageHandler/syncStep2.js

@@ -0,0 +1,28 @@
+import { stringifyStructs, integrateRemoteStructs } from './integrateRemoteStructs.js'
+import { readDeleteSet } from './deleteSet.js'
+
+export function stringifySyncStep2 (y, decoder, strBuilder) {
+  strBuilder.push('     - auth: ' + decoder.readVarString())
+  strBuilder.push('  == OS:')
+  stringifyStructs(y, decoder, strBuilder)
+  // write DS to string
+  strBuilder.push('  == DS:')
+  let len = decoder.readUint32()
+  for (let i = 0; i < len; i++) {
+    let user = decoder.readVarUint()
+    strBuilder.push(`    User: ${user}: `)
+    let len2 = decoder.readUint32()
+    for (let j = 0; j < len2; j++) {
+      let from = decoder.readVarUint()
+      let to = decoder.readVarUint()
+      let gc = decoder.readUint8() === 1
+      strBuilder.push(`[${from}, ${to}, ${gc}]`)
+    }
+  }
+}
+
+export function readSyncStep2 (decoder, encoder, y, senderConn, sender) {
+  integrateRemoteStructs(decoder, encoder, y)
+  readDeleteSet(y, decoder)
+  y.connector._setSyncedWith(sender)
+}

src/Notes.md

@@ -1,12 +0,0 @@
-
-# Notes
-
-### Terminology
-
-* DB: DataBase that holds all the information of the shared object. It is devided into the OS, DS, and SS. This can be a persistent database or an in-memory database. Depending on the type of database, it could make sense to store OS, DS, and SS in different tables, or maybe different databases.
-* OS: OperationStore holds all the operations. An operation is a js object with a fixed number of name fields.
-* DS: DeleteStore holds the information about which operations are deleted and which operations were garbage collected (no longer available in the OS).
-* SS: StateSet holds the current state of the OS. SS.getState(username) refers to the amount of operations that were received by that respective user.
-* Op: Operation defines an action on a shared type. But it is also the format in which we store the model of a type. This is why it is also called a Struct/Structure.
-* Type and Structure: We crearly distinguish between type and structure. Short explanation: A type (e.g. Strings, Numbers) have a number of functions that you can apply on them. (+) is well defined on both of them. They are *modeled* by a structure - the functions really change the structure of a type. Types can be implemented differently but still provide the same functionality. In Yjs, almost all types are realized as a doubly linked list (on which Yjs can provide eventual convergence)
-*

src/Persistence.js

@@ -0,0 +1,47 @@
+// import BinaryEncoder from './Binary/Encoder.js'
+
+export default function extendPersistence (Y) {
+  class AbstractPersistence {
+    constructor (y, opts) {
+      this.y = y
+      this.opts = opts
+      this.saveOperationsBuffer = []
+      this.log = Y.debug('y:persistence')
+    }
+
+    saveToMessageQueue (binary) {
+      this.log('Room %s: Save message to message queue', this.y.options.connector.room)
+    }
+
+    saveOperations (ops) {
+      ops = ops.map(function (op) {
+        return Y.Struct[op.struct].encode(op)
+      })
+      /*
+      const saveOperations = () => {
+        if (this.saveOperationsBuffer.length > 0) {
+          let encoder = new BinaryEncoder()
+          encoder.writeVarString(this.opts.room)
+          encoder.writeVarString('update')
+          let ops = this.saveOperationsBuffer
+          this.saveOperationsBuffer = []
+          let length = ops.length
+          encoder.writeUint32(length)
+          for (var i = 0; i < length; i++) {
+            let op = ops[i]
+            Y.Struct[op.struct].binaryEncode(encoder, op)
+          }
+          this.saveToMessageQueue(encoder.createBuffer())
+        }
+      }
+      */
+      if (this.saveOperationsBuffer.length === 0) {
+        this.saveOperationsBuffer = ops
+      } else {
+        this.saveOperationsBuffer = this.saveOperationsBuffer.concat(ops)
+      }
+    }
+  }
+
+  Y.AbstractPersistence = AbstractPersistence
+}

src/SpecHelper.js

@@ -1,384 +0,0 @@
-/* eslint-env browser, jasmine */
-
-/*
-  This is just a compilation of functions that help to test this library!
-*/
-
-// When testing, you store everything on the global object. We call it g
-
-var Y = require('./y.js')
-require('../../y-memory/src/Memory.js')(Y)
-require('../../y-array/src/Array.js')(Y)
-require('../../y-map/src/Map.js')(Y)
-require('../../y-indexeddb/src/IndexedDB.js')(Y)
-if (typeof window === 'undefined') {
-  require('../../y-leveldb/src/LevelDB.js')(Y)
-}
-module.exports = Y
-
-var g
-if (typeof global !== 'undefined') {
-  g = global
-} else if (typeof window !== 'undefined') {
-  g = window
-} else {
-  throw new Error('No global object?')
-}
-g.g = g
-
-// Helper methods for the random number generator
-Math.seedrandom = require('seedrandom')
-
-g.generateRandomSeed = function generateRandomSeed () {
-  var seed
-  if (typeof window !== 'undefined' && window.location.hash.length > 1) {
-    seed = window.location.hash.slice(1) // first character is the hash!
-    console.warn('Using random seed that was specified in the url!')
-  } else {
-    seed = JSON.stringify(Math.random())
-  }
-  console.info('Using random seed: ' + seed)
-  g.setRandomSeed(seed)
-}
-
-g.setRandomSeed = function setRandomSeed (seed) {
-  Math.seedrandom.currentSeed = seed
-  Math.seedrandom(Math.seedrandom.currentSeed, { global: true })
-}
-
-g.generateRandomSeed()
-
-g.YConcurrency_TestingMode = true
-
-jasmine.DEFAULT_TIMEOUT_INTERVAL = 200000
-
-g.describeManyTimes = function describeManyTimes (times, name, f) {
-  for (var i = 0; i < times; i++) {
-    describe(name, f)
-  }
-}
-
-/*
-  Wait for a specified amount of time (in ms). defaults to 5ms
-*/
-function wait (t) {
-  if (t == null) {
-    t = 0
-  }
-  return new Promise(function (resolve) {
-    setTimeout(function () {
-      resolve()
-    }, t)
-  })
-}
-g.wait = wait
-
-g.databases = ['memory']
-if (typeof window !== 'undefined') {
-  g.databases.push('indexeddb')
-} else {
-  g.databases.push('leveldb')
-}
-/*
-  returns a random element of o.
-  works on Object, and Array
-*/
-function getRandom (o) {
-  if (o instanceof Array) {
-    return o[Math.floor(Math.random() * o.length)]
-  } else if (o.constructor === Object) {
-    return o[getRandom(Object.keys(o))]
-  }
-}
-g.getRandom = getRandom
-
-function getRandomNumber (n) {
-  if (n == null) {
-    n = 9999
-  }
-  return Math.floor(Math.random() * n)
-}
-g.getRandomNumber = getRandomNumber
-
-function getRandomString () {
-  var chars = 'abcdefghijklmnopqrstuvwxyzäüöABCDEFGHIJKLMNOPQRSTUVWXYZÄÜÖ'
-  var char = chars[getRandomNumber(chars.length)] // ü\n\n\n\n\n\n\n'
-  var length = getRandomNumber(7)
-  var string = ''
-  for (var i = 0; i < length; i++) {
-    string += char
-  }
-  return string
-}
-g.getRandomString = getRandomString
-
-function * applyTransactions (relAmount, numberOfTransactions, objects, users, transactions, noReconnect) {
-  g.generateRandomSeed() // create a new seed, so we can re-create the behavior
-  for (var i = 0; i < numberOfTransactions * relAmount + 1; i++) {
-    var r = Math.random()
-    if (r > 0.95) {
-      // 10% chance of toggling concurrent user interactions.
-      // There will be an artificial delay until ops can be executed by the type,
-      // therefore, operations of the database will be (pre)transformed until user operations arrive
-      yield (function simulateConcurrentUserInteractions (type) {
-        if (type.eventHandler.awaiting === 0 && type.eventHandler._debuggingAwaiting !== true) {
-          type.eventHandler.awaiting = 1
-          type.eventHandler._debuggingAwaiting = true
-        } else {
-          // fixAwaitingInType will handle _debuggingAwaiting
-          return fixAwaitingInType(type)
-        }
-      })(getRandom(objects))
-    } else if (r >= 0.5) {
-      // 40% chance to flush
-      yield Y.utils.globalRoom.flushOne() // flushes for some user.. (not necessarily 0)
-    } else if (noReconnect || r >= 0.05) {
-      // 45% chance to create operation
-      var done = getRandom(transactions)(getRandom(objects))
-      if (done != null) {
-        yield done
-      } else {
-        yield wait()
-      }
-      yield Y.utils.globalRoom.whenTransactionsFinished()
-    } else {
-      // 5% chance to disconnect/reconnect
-      var u = getRandom(users)
-      yield Promise.all(objects.map(fixAwaitingInType))
-      if (u.connector.isDisconnected()) {
-        yield u.reconnect()
-      } else {
-        yield u.disconnect()
-      }
-      yield Promise.all(objects.map(fixAwaitingInType))
-    }
-  }
-}
-
-function fixAwaitingInType (type) {
-  return new Promise(function (resolve) {
-    type.os.whenTransactionsFinished().then(function () {
-      // _debuggingAwaiting artificially increases the awaiting property. We need to make sure that we only do that once / reverse the effect once
-      type.os.requestTransaction(function * () {
-        if (type.eventHandler.awaiting > 0 && type.eventHandler._debuggingAwaiting === true) {
-          type.eventHandler._debuggingAwaiting = false
-          yield* type.eventHandler.awaitOps(this, function * () { /* mock function */ })
-        }
-        wait(50).then(type.os.whenTransactionsFinished()).then(wait(50)).then(resolve)
-      })
-    })
-  })
-}
-g.fixAwaitingInType = fixAwaitingInType
-
-g.applyRandomTransactionsNoGCNoDisconnect = async(function * applyRandomTransactions (users, objects, transactions, numberOfTransactions) {
-  yield* applyTransactions(1, numberOfTransactions, objects, users, transactions, true)
-  yield Y.utils.globalRoom.flushAll()
-  yield Promise.all(objects.map(fixAwaitingInType))
-})
-
-g.applyRandomTransactionsAllRejoinNoGC = async(function * applyRandomTransactions (users, objects, transactions, numberOfTransactions) {
-  yield* applyTransactions(1, numberOfTransactions, objects, users, transactions)
-  yield Promise.all(objects.map(fixAwaitingInType))
-  yield Y.utils.globalRoom.flushAll()
-  yield Promise.all(objects.map(fixAwaitingInType))
-  for (var u in users) {
-    yield Promise.all(objects.map(fixAwaitingInType))
-    yield users[u].reconnect()
-    yield Promise.all(objects.map(fixAwaitingInType))
-  }
-  yield Promise.all(objects.map(fixAwaitingInType))
-  yield Y.utils.globalRoom.flushAll()
-  yield Promise.all(objects.map(fixAwaitingInType))
-  yield g.garbageCollectAllUsers(users)
-})
-
-g.applyRandomTransactionsWithGC = async(function * applyRandomTransactions (users, objects, transactions, numberOfTransactions) {
-  yield* applyTransactions(1, numberOfTransactions, objects, users.slice(1), transactions)
-  yield Y.utils.globalRoom.flushAll()
-  yield Promise.all(objects.map(fixAwaitingInType))
-  for (var u in users) {
-    // TODO: here, we enforce that two users never sync at the same time with u[0]
-    //       enforce that in the connector itself!
-    yield users[u].reconnect()
-  }
-  yield Y.utils.globalRoom.flushAll()
-  yield Promise.all(objects.map(fixAwaitingInType))
-  yield g.garbageCollectAllUsers(users)
-})
-
-g.garbageCollectAllUsers = async(function * garbageCollectAllUsers (users) {
-  yield Y.utils.globalRoom.flushAll()
-  for (var i in users) {
-    yield users[i].db.emptyGarbageCollector()
-  }
-})
-
-g.compareAllUsers = async(function * compareAllUsers (users) {
-  var s1, s2 // state sets
-  var ds1, ds2 // delete sets
-  var allDels1, allDels2 // all deletions
-  var db1 = [] // operation store of user1
-
-  // t1 and t2 basically do the same. They define t[1,2], ds[1,2], and allDels[1,2]
-  function * t1 () {
-    s1 = yield* this.getStateSet()
-    ds1 = yield* this.getDeleteSet()
-    allDels1 = []
-    yield* this.ds.iterate(this, null, null, function * (d) {
-      allDels1.push(d)
-    })
-  }
-  function * t2 () {
-    s2 = yield* this.getStateSet()
-    ds2 = yield* this.getDeleteSet()
-    allDels2 = []
-    yield* this.ds.iterate(this, null, null, function * (d) {
-      allDels2.push(d)
-    })
-  }
-  yield Y.utils.globalRoom.flushAll()
-  yield g.garbageCollectAllUsers(users)
-  yield Y.utils.globalRoom.flushAll()
-  var buffer = Y.utils.globalRoom.buffers
-  for (var name in buffer) {
-    if (buffer[name].length > 0) {
-      // not all ops were transmitted..
-      debugger // eslint-disable-line
-    }
-  }
-
-  for (var uid = 0; uid < users.length; uid++) {
-    var u = users[uid]
-    u.db.requestTransaction(function * () {
-      var sv = yield* this.getStateVector()
-      for (var s of sv) {
-        yield* this.updateState(s.user)
-      }
-      // compare deleted ops against deleteStore
-      yield* this.os.iterate(this, null, null, function * (o) {
-        if (o.deleted === true) {
-          expect(yield* this.isDeleted(o.id)).toBeTruthy()
-        }
-      })
-      // compare deleteStore against deleted ops
-      var ds = []
-      yield* this.ds.iterate(this, null, null, function * (d) {
-        ds.push(d)
-      })
-      for (var j in ds) {
-        var d = ds[j]
-        for (var i = 0; i < d.len; i++) {
-          var o = yield* this.getInsertion([d.id[0], d.id[1] + i])
-          // gc'd or deleted
-          if (d.gc) {
-            expect(o).toBeFalsy()
-          } else {
-            expect(o.deleted).toBeTruthy()
-          }
-        }
-      }
-    })
-    // compare allDels tree
-    if (s1 == null) {
-      u.db.requestTransaction(function * () {
-        yield* t1.call(this)
-        yield* this.os.iterate(this, null, null, function * (o) {
-          o = Y.utils.copyObject(o)
-          delete o.origin
-          delete o.originOf
-          db1.push(o)
-        })
-      })
-    } else {
-      u.db.requestTransaction(function * () {
-        yield* t2.call(this)
-        var db2 = []
-        yield* this.os.iterate(this, null, null, function * (o) {
-          o = Y.utils.copyObject(o)
-          delete o.origin
-          delete o.originOf
-          db2.push(o)
-        })
-        expect(s1).toEqual(s2)
-        expect(allDels1).toEqual(allDels2) // inner structure
-        expect(ds1).toEqual(ds2) // exported structure
-        db2.forEach((o, i) => {
-          expect(db1[i]).toEqual(o)
-        })
-      })
-    }
-    yield u.db.whenTransactionsFinished()
-  }
-})
-
-g.createUsers = async(function * createUsers (self, numberOfUsers, database, initType) {
-  if (Y.utils.globalRoom.users[0] != null) {
-    yield Y.utils.globalRoom.flushAll()
-  }
-  // destroy old users
-  for (var u in Y.utils.globalRoom.users) {
-    Y.utils.globalRoom.users[u].y.destroy()
-  }
-  self.users = null
-
-  var promises = []
-  for (var i = 0; i < numberOfUsers; i++) {
-    promises.push(Y({
-      db: {
-        name: database,
-        namespace: 'User ' + i,
-        cleanStart: true,
-        gcTimeout: -1
-      },
-      connector: {
-        name: 'Test',
-        debug: false
-      },
-      share: {
-        root: initType || 'Map'
-      }
-    }))
-  }
-  self.users = yield Promise.all(promises)
-  self.types = self.users.map(function (u) { return u.share.root })
-  return self.users
-})
-
-/*
-  Until async/await arrives in js, we use this function to wait for promises
-  by yielding them.
-*/
-function async (makeGenerator) {
-  return function (arg) {
-    var generator = makeGenerator.apply(this, arguments)
-
-    function handle (result) {
-      if (result.done) return Promise.resolve(result.value)
-
-      return Promise.resolve(result.value).then(function (res) {
-        return handle(generator.next(res))
-      }, function (err) {
-        return handle(generator.throw(err))
-      })
-    }
-    try {
-      return handle(generator.next())
-    } catch (ex) {
-      generator.throw(ex)
-      // return Promise.reject(ex)
-    }
-  }
-}
-g.async = async
-
-function logUsers (self) {
-  if (self.constructor === Array) {
-    self = {users: self}
-  }
-  self.users[0].db.logTable()
-  self.users[1].db.logTable()
-  self.users[2].db.logTable()
-}
-
-g.logUsers = logUsers

src/Store/DeleteStore.js

@@ -0,0 +1,125 @@
+import Tree from '../Util/Tree.js'
+import ID from '../Util/ID.js'
+
+class DSNode {
+  constructor (id, len, gc) {
+    this._id = id
+    this.len = len
+    this.gc = gc
+  }
+  clone () {
+    return new DSNode(this._id, this.len, this.gc)
+  }
+}
+
+export default class DeleteStore extends Tree {
+  logTable () {
+    const deletes = []
+    this.iterate(null, null, function (n) {
+      deletes.push({
+        user: n._id.user,
+        clock: n._id.clock,
+        len: n.len,
+        gc: n.gc
+      })
+    })
+    console.table(deletes)
+  }
+  isDeleted (id) {
+    var n = this.findWithUpperBound(id)
+    return n !== null && n._id.user === id.user && id.clock < n._id.clock + n.len
+  }
+  /*
+   * Mark an operation as deleted. returns the deleted node
+   */
+  markDeleted (id, length) {
+    if (length == null) {
+      throw new Error('length must be defined')
+    }
+    var n = this.findWithUpperBound(id)
+    if (n != null && n._id.user === id.user) {
+      if (n._id.clock <= id.clock && id.clock <= n._id.clock + n.len) {
+        // id is in n's range
+        var diff = id.clock + length - (n._id.clock + n.len) // overlapping right
+        if (diff > 0) {
+          // id+length overlaps n
+          if (!n.gc) {
+            n.len += diff
+          } else {
+            diff = n._id.clock + n.len - id.clock // overlapping left (id till n.end)
+            if (diff < length) {
+              // a partial deletion
+              let nId = id.clone()
+              nId.clock += diff
+              n = new DSNode(nId, length - diff, false)
+              this.put(n)
+            } else {
+              // already gc'd
+              throw new Error(
+                'DS reached an inconsistent state. Please report this issue!'
+              )
+            }
+          }
+        } else {
+          // no overlapping, already deleted
+          return n
+        }
+      } else {
+        // cannot extend left (there is no left!)
+        n = new DSNode(id, length, false)
+        this.put(n) // TODO: you double-put !!
+      }
+    } else {
+      // cannot extend left
+      n = new DSNode(id, length, false)
+      this.put(n)
+    }
+    // can extend right?
+    var next = this.findNext(n._id)
+    if (
+      next != null &&
+      n._id.user === next._id.user &&
+      n._id.clock + n.len >= next._id.clock
+    ) {
+      diff = n._id.clock + n.len - next._id.clock // from next.start to n.end
+      while (diff >= 0) {
+        // n overlaps with next
+        if (next.gc) {
+          // gc is stronger, so reduce length of n
+          n.len -= diff
+          if (diff >= next.len) {
+            // delete the missing range after next
+            diff = diff - next.len // missing range after next
+            if (diff > 0) {
+              this.put(n) // unneccessary? TODO!
+              this.markDeleted(new ID(next._id.user, next._id.clock + next.len), diff)
+            }
+          }
+          break
+        } else {
+          // we can extend n with next
+          if (diff > next.len) {
+            // n is even longer than next
+            // get next.next, and try to extend it
+            var _next = this.findNext(next._id)
+            this.delete(next._id)
+            if (_next == null || n._id.user !== _next._id.user) {
+              break
+            } else {
+              next = _next
+              diff = n._id.clock + n.len - next._id.clock // from next.start to n.end
+              // continue!
+            }
+          } else {
+            // n just partially overlaps with next. extend n, delete next, and break this loop
+            n.len += next.len - diff
+            this.delete(next._id)
+            break
+          }
+        }
+      }
+    }
+    this.put(n)
+    return n
+  }
+}

src/Store/OperationStore.js

@@ -0,0 +1,85 @@
+import Tree from '../Util/Tree.js'
+import RootID from '../Util/RootID.js'
+import { getStruct } from '../Util/structReferences.js'
+import { logID } from '../MessageHandler/messageToString.js'
+
+export default class OperationStore extends Tree {
+  constructor (y) {
+    super()
+    this.y = y
+  }
+  logTable () {
+    const items = []
+    this.iterate(null, null, function (item) {
+      items.push({
+        id: logID(item),
+        origin: logID(item._origin === null ? null : item._origin._lastId),
+        left: logID(item._left === null ? null : item._left._lastId),
+        right: logID(item._right),
+        right_origin: logID(item._right_origin),
+        parent: logID(item._parent),
+        parentSub: item._parentSub,
+        deleted: item._deleted,
+        content: JSON.stringify(item._content)
+      })
+    })
+    console.table(items)
+  }
+  get (id) {
+    let struct = this.find(id)
+    if (struct === null && id instanceof RootID) {
+      const Constr = getStruct(id.type)
+      const y = this.y
+      struct = new Constr()
+      struct._id = id
+      struct._parent = y
+      y.transact(() => {
+        struct._integrate(y)
+      })
+      this.put(struct)
+    }
+    return struct
+  }
+  // Use getItem for structs with _length > 1
+  getItem (id) {
+    var item = this.findWithUpperBound(id)
+    if (item === null) {
+      return null
+    }
+    const itemID = item._id
+    if (id.user === itemID.user && id.clock < itemID.clock + item._length) {
+      return item
+    } else {
+      return null
+    }
+  }
+  // Return an insertion such that id is the first element of content
+  // This function manipulates an item, if necessary
+  getItemCleanStart (id) {
+    var ins = this.getItem(id)
+    if (ins === null || ins._length === 1) {
+      return ins
+    }
+    const insID = ins._id
+    if (insID.clock === id.clock) {
+      return ins
+    } else {
+      return ins._splitAt(this.y, id.clock - insID.clock)
+    }
+  }
+  // Return an insertion such that id is the last element of content
+  // This function manipulates an operation, if necessary
+  getItemCleanEnd (id) {
+    var ins = this.getItem(id)
+    if (ins === null || ins._length === 1) {
+      return ins
+    }
+    const insID = ins._id
+    if (insID.clock + ins._length - 1 === id.clock) {
+      return ins
+    } else {
+      ins._splitAt(this.y, id.clock - insID.clock + 1)
+      return ins
+    }
+  }
+}

src/Store/StateStore.js

@@ -0,0 +1,47 @@
+import ID from '../Util/ID.js'
+
+export default class StateStore {
+  constructor (y) {
+    this.y = y
+    this.state = new Map()
+  }
+  logTable () {
+    const entries = []
+    for (let [user, state] of this.state) {
+      entries.push({
+        user, state
+      })
+    }
+    console.table(entries)
+  }
+  getNextID (len) {
+    const user = this.y.userID
+    const state = this.getState(user)
+    this.setState(user, state + len)
+    return new ID(user, state)
+  }
+  updateRemoteState (struct) {
+    let user = struct._id.user
+    let userState = this.state.get(user)
+    while (struct !== null && struct._id.clock === userState) {
+      userState += struct._length
+      struct = this.y.os.get(new ID(user, userState))
+    }
+    this.state.set(user, userState)
+  }
+  getState (user) {
+    let state = this.state.get(user)
+    if (state == null) {
+      return 0
+    }
+    return state
+  }
+  setState (user, state) {
+    // TODO: modify missingi structs here
+    const beforeState = this.y._transaction.beforeState
+    if (!beforeState.has(user)) {
+      beforeState.set(user, this.getState(user))
+    }
+    this.state.set(user, state)
+  }
+}

src/Struct.js

@@ -1,410 +0,0 @@
-/* @flow */
-'use strict'
-
-/*
- An operation also defines the structure of a type. This is why operation and
- structure are used interchangeably here.
-
- It must be of the type Object. I hope to achieve some performance
- improvements when working on databases that support the json format.
-
- An operation must have the following properties:
-
- * encode
-     - Encode the structure in a readable format (preferably string- todo)
- * decode (todo)
-     - decode structure to json
- * execute
-     - Execute the semantics of an operation.
- * requiredOps
-     - Operations that are required to execute this operation.
-*/
-module.exports = function (Y/* :any */) {
-  var Struct = {
-    /* This is the only operation that is actually not a structure, because
-    it is not stored in the OS. This is why it _does not_ have an id
-
-    op = {
-      target: Id
-    }
-    */
-    Delete: {
-      encode: function (op) {
-        return op
-      },
-      requiredOps: function (op) {
-        return [] // [op.target]
-      },
-      execute: function * (op) {
-        return yield* this.deleteOperation(op.target, op.length || 1)
-      }
-    },
-    Insert: {
-      /* {
-          content: [any],
-          opContent: Id,
-          id: Id,
-          left: Id,
-          origin: Id,
-          right: Id,
-          parent: Id,
-          parentSub: string (optional), // child of Map type
-        }
-      */
-      encode: function (op/* :Insertion */) /* :Insertion */ {
-        // TODO: you could not send the "left" property, then you also have to
-        // "op.left = null" in $execute or $decode
-        var e/* :any */ = {
-          id: op.id,
-          left: op.left,
-          right: op.right,
-          origin: op.origin,
-          parent: op.parent,
-          struct: op.struct
-        }
-        if (op.parentSub != null) {
-          e.parentSub = op.parentSub
-        }
-        if (op.hasOwnProperty('opContent')) {
-          e.opContent = op.opContent
-        } else {
-          e.content = op.content.slice()
-        }
-
-        return e
-      },
-      requiredOps: function (op) {
-        var ids = []
-        if (op.left != null) {
-          ids.push(op.left)
-        }
-        if (op.right != null) {
-          ids.push(op.right)
-        }
-        if (op.origin != null && !Y.utils.compareIds(op.left, op.origin)) {
-          ids.push(op.origin)
-        }
-        // if (op.right == null && op.left == null) {
-        ids.push(op.parent)
-
-        if (op.opContent != null) {
-          ids.push(op.opContent)
-        }
-        return ids
-      },
-      getDistanceToOrigin: function * (op) {
-        if (op.left == null) {
-          return 0
-        } else {
-          var d = 0
-          var o = yield* this.getInsertion(op.left)
-          while (!Y.utils.matchesId(o, op.origin)) {
-            d++
-            if (o.left == null) {
-              break
-            } else {
-              o = yield* this.getInsertion(o.left)
-            }
-          }
-          return d
-        }
-      },
-      /*
-      # $this has to find a unique position between origin and the next known character
-      # case 1: $origin equals $o.origin: the $creator parameter decides if left or right
-      #         let $OL= [o1,o2,o3,o4], whereby $this is to be inserted between o1 and o4
-      #         o2,o3 and o4 origin is 1 (the position of o2)
-      #         there is the case that $this.creator < o2.creator, but o3.creator < $this.creator
-      #         then o2 knows o3. Since on another client $OL could be [o1,o3,o4] the problem is complex
-      #         therefore $this would be always to the right of o3
-      # case 2: $origin < $o.origin
-      #         if current $this insert_position > $o origin: $this ins
-      #         else $insert_position will not change
-      #         (maybe we encounter case 1 later, then this will be to the right of $o)
-      # case 3: $origin > $o.origin
-      #         $this insert_position is to the left of $o (forever!)
-      */
-      execute: function * (op) {
-        var i // loop counter
-
-        // during this function some ops may get split into two pieces (e.g. with getInsertionCleanEnd)
-        // We try to merge them later, if possible
-        var tryToRemergeLater = []
-
-        if (op.origin != null) { // TODO: !== instead of !=
-          // we save in origin that op originates in it
-          // we need that later when we eventually garbage collect origin (see transaction)
-          var origin = yield* this.getInsertionCleanEnd(op.origin)
-          if (origin.originOf == null) {
-            origin.originOf = []
-          }
-          origin.originOf.push(op.id)
-          yield* this.setOperation(origin)
-          if (origin.right != null) {
-            tryToRemergeLater.push(origin.right)
-          }
-        }
-        var distanceToOrigin = i = yield* Struct.Insert.getDistanceToOrigin.call(this, op) // most cases: 0 (starts from 0)
-
-        // now we begin to insert op in the list of insertions..
-        var o
-        var parent
-        var start
-
-        // find o. o is the first conflicting operation
-        if (op.left != null) {
-          o = yield* this.getInsertionCleanEnd(op.left)
-          if (!Y.utils.compareIds(op.left, op.origin) && o.right != null) {
-            // only if not added previously
-            tryToRemergeLater.push(o.right)
-          }
-          o = (o.right == null) ? null : yield* this.getOperation(o.right)
-        } else { // left == null
-          parent = yield* this.getOperation(op.parent)
-          let startId = op.parentSub ? parent.map[op.parentSub] : parent.start
-          start = startId == null ? null : yield* this.getOperation(startId)
-          o = start
-        }
-
-        // make sure to split op.right if necessary (also add to tryCombineWithLeft)
-        if (op.right != null) {
-          tryToRemergeLater.push(op.right)
-          yield* this.getInsertionCleanStart(op.right)
-        }
-
-        // handle conflicts
-        while (true) {
-          if (o != null && !Y.utils.compareIds(o.id, op.right)) {
-            var oOriginDistance = yield* Struct.Insert.getDistanceToOrigin.call(this, o)
-            if (oOriginDistance === i) {
-              // case 1
-              if (o.id[0] < op.id[0]) {
-                op.left = Y.utils.getLastId(o)
-                distanceToOrigin = i + 1 // just ignore o.content.length, doesn't make a difference
-              }
-            } else if (oOriginDistance < i) {
-              // case 2
-              if (i - distanceToOrigin <= oOriginDistance) {
-                op.left = Y.utils.getLastId(o)
-                distanceToOrigin = i + 1 // just ignore o.content.length, doesn't make a difference
-              }
-            } else {
-              break
-            }
-            i++
-            if (o.right != null) {
-              o = yield* this.getInsertion(o.right)
-            } else {
-              o = null
-            }
-          } else {
-            break
-          }
-        }
-
-        // reconnect..
-        var left = null
-        var right = null
-        if (parent == null) {
-          parent = yield* this.getOperation(op.parent)
-        }
-
-        // reconnect left and set right of op
-        if (op.left != null) {
-          left = yield* this.getInsertion(op.left)
-          // link left
-          op.right = left.right
-          left.right = op.id
-
-          yield* this.setOperation(left)
-        } else {
-          // set op.right from parent, if necessary
-          op.right = op.parentSub ? parent.map[op.parentSub] || null : parent.start
-        }
-        // reconnect right
-        if (op.right != null) {
-          // TODO: wanna connect right too?
-          right = yield* this.getOperation(op.right)
-          right.left = Y.utils.getLastId(op)
-
-          // if right exists, and it is supposed to be gc'd. Remove it from the gc
-          if (right.gc != null) {
-            if (right.content != null && right.content.length > 1) {
-              right = yield* this.getInsertionCleanEnd(right.id)
-            }
-            this.store.removeFromGarbageCollector(right)
-          }
-          yield* this.setOperation(right)
-        }
-
-        // update parents .map/start/end properties
-        if (op.parentSub != null) {
-          if (left == null) {
-            parent.map[op.parentSub] = op.id
-            yield* this.setOperation(parent)
-          }
-          // is a child of a map struct.
-          // Then also make sure that only the most left element is not deleted
-          // We do not call the type in this case (this is what the third parameter is for)
-          if (op.right != null) {
-            yield* this.deleteOperation(op.right, 1, true)
-          }
-          if (op.left != null) {
-            yield* this.deleteOperation(op.id, 1, true)
-          }
-        } else {
-          if (right == null || left == null) {
-            if (right == null) {
-              parent.end = Y.utils.getLastId(op)
-            }
-            if (left == null) {
-              parent.start = op.id
-            }
-            yield* this.setOperation(parent)
-          }
-        }
-
-        // try to merge original op.left and op.origin
-        for (let i = 0; i < tryToRemergeLater.length; i++) {
-          var m = yield* this.getOperation(tryToRemergeLater[i])
-          yield* this.tryCombineWithLeft(m)
-        }
-      }
-    },
-    List: {
-      /*
-      {
-        start: null,
-        end: null,
-        struct: "List",
-        type: "",
-        id: this.os.getNextOpId(1)
-      }
-      */
-      create: function (id) {
-        return {
-          start: null,
-          end: null,
-          struct: 'List',
-          id: id
-        }
-      },
-      encode: function (op) {
-        var e = {
-          struct: 'List',
-          id: op.id,
-          type: op.type
-        }
-        if (op.requires != null) {
-          e.requires = op.requires
-        }
-        if (op.info != null) {
-          e.info = op.info
-        }
-        return e
-      },
-      requiredOps: function () {
-        /*
-        var ids = []
-        if (op.start != null) {
-          ids.push(op.start)
-        }
-        if (op.end != null){
-          ids.push(op.end)
-        }
-        return ids
-        */
-        return []
-      },
-      execute: function * (op) {
-        op.start = null
-        op.end = null
-      },
-      ref: function * (op, pos) {
-        if (op.start == null) {
-          return null
-        }
-        var res = null
-        var o = yield* this.getOperation(op.start)
-
-        while (true) {
-          if (!o.deleted) {
-            res = o
-            pos--
-          }
-          if (pos >= 0 && o.right != null) {
-            o = yield* this.getOperation(o.right)
-          } else {
-            break
-          }
-        }
-        return res
-      },
-      map: function * (o, f) {
-        o = o.start
-        var res = []
-        while (o != null) { // TODO: change to != (at least some convention)
-          var operation = yield* this.getOperation(o)
-          if (!operation.deleted) {
-            res.push(f(operation))
-          }
-          o = operation.right
-        }
-        return res
-      }
-    },
-    Map: {
-      /*
-        {
-          map: {},
-          struct: "Map",
-          type: "",
-          id: this.os.getNextOpId(1)
-        }
-      */
-      create: function (id) {
-        return {
-          id: id,
-          map: {},
-          struct: 'Map'
-        }
-      },
-      encode: function (op) {
-        var e = {
-          struct: 'Map',
-          type: op.type,
-          id: op.id,
-          map: {} // overwrite map!!
-        }
-        if (op.requires != null) {
-          e.requires = op.requires
-        }
-        if (op.info != null) {
-          e.info = op.info
-        }
-        return e
-      },
-      requiredOps: function () {
-        return []
-      },
-      execute: function * () {},
-      /*
-        Get a property by name
-      */
-      get: function * (op, name) {
-        var oid = op.map[name]
-        if (oid != null) {
-          var res = yield* this.getOperation(oid)
-          if (res == null || res.deleted) {
-            return void 0
-          } else if (res.opContent == null) {
-            return res.content[0]
-          } else {
-            return yield* this.getType(res.opContent)
-          }
-        }
-      }
-    }
-  }
-  Y.Struct = Struct
-}

src/Struct/Delete.js

@@ -0,0 +1,84 @@
+import { getReference } from '../Util/structReferences.js'
+import ID from '../Util/ID.js'
+import { logID } from '../MessageHandler/messageToString.js'
+
+/**
+ * Delete all items in an ID-range
+ * TODO: implement getItemCleanStartNode for better performance (only one lookup)
+ */
+export function deleteItemRange (y, user, clock, range) {
+  const createDelete = y.connector._forwardAppliedStructs
+  let item = y.os.getItemCleanStart(new ID(user, clock))
+  if (item !== null) {
+    if (!item._deleted) {
+      item._splitAt(y, range)
+      item._delete(y, createDelete)
+    }
+    let itemLen = item._length
+    range -= itemLen
+    clock += itemLen
+    if (range > 0) {
+      let node = y.os.findNode(new ID(user, clock))
+      while (node !== null && range > 0 && node.val._id.equals(new ID(user, clock))) {
+        const nodeVal = node.val
+        if (!nodeVal._deleted) {
+          nodeVal._splitAt(y, range)
+          nodeVal._delete(y, createDelete)
+        }
+        const nodeLen = nodeVal._length
+        range -= nodeLen
+        clock += nodeLen
+        node = node.next()
+      }
+    }
+  }
+}
+
+/**
+ * Delete is not a real struct. It will not be saved in OS
+ */
+export default class Delete {
+  constructor () {
+    this._target = null
+    this._length = null
+  }
+  _fromBinary (y, decoder) {
+    // TODO: set target, and add it to missing if not found
+    // There is an edge case in p2p networks!
+    const targetID = decoder.readID()
+    this._targetID = targetID
+    this._length = decoder.readVarUint()
+    if (y.os.getItem(targetID) === null) {
+      return [targetID]
+    } else {
+      return []
+    }
+  }
+  _toBinary (encoder) {
+    encoder.writeUint8(getReference(this.constructor))
+    encoder.writeID(this._targetID)
+    encoder.writeVarUint(this._length)
+  }
+  /**
+   * - If created remotely (a remote user deleted something),
+   *   this Delete is applied to all structs in id-range.
+   * - If created lokally (e.g. when y-array deletes a range of elements),
+   *   this struct is broadcasted only (it is already executed)
+   */
+  _integrate (y, locallyCreated = false) {
+    if (!locallyCreated) {
+      // from remote
+      const id = this._targetID
+      deleteItemRange(y, id.user, id.clock, this._length)
+    } else {
+      // from local
+      y.connector.broadcastStruct(this)
+    }
+    if (y.persistence !== null) {
+      y.persistence.saveOperations(this)
+    }
+  }
+  _logString () {
+    return `Delete - target: ${logID(this._targetID)}, len: ${this._length}`
+  }
+}

src/Struct/Item.js

@@ -0,0 +1,327 @@
+import { getReference } from '../Util/structReferences.js'
+import ID from '../Util/ID.js'
+import { RootFakeUserID } from '../Util/RootID.js'
+import Delete from './Delete.js'
+import { transactionTypeChanged } from '../Transaction.js'
+
+/**
+ * Helper utility to split an Item (see _splitAt)
+ * - copy all properties from a to b
+ * - connect a to b
+ * - assigns the correct _id
+ * - save b to os
+ */
+export function splitHelper (y, a, b, diff) {
+  const aID = a._id
+  b._id = new ID(aID.user, aID.clock + diff)
+  b._origin = a
+  b._left = a
+  b._right = a._right
+  if (b._right !== null) {
+    b._right._left = b
+  }
+  b._right_origin = a._right_origin
+  // do not set a._right_origin, as this will lead to problems when syncing
+  a._right = b
+  b._parent = a._parent
+  b._parentSub = a._parentSub
+  b._deleted = a._deleted
+  // now search all relevant items to the right and update origin
+  // if origin is not it foundOrigins, we don't have to search any longer
+  let foundOrigins = new Set()
+  foundOrigins.add(a)
+  let o = b._right
+  while (o !== null && foundOrigins.has(o._origin)) {
+    if (o._origin === a) {
+      o._origin = b
+    }
+    foundOrigins.add(o)
+    o = o._right
+  }
+  y.os.put(b)
+}
+
+export default class Item {
+  constructor () {
+    this._id = null
+    this._origin = null
+    this._left = null
+    this._right = null
+    this._right_origin = null
+    this._parent = null
+    this._parentSub = null
+    this._deleted = false
+  }
+  /**
+   * Copy the effect of struct
+   */
+  _copy () {
+    let struct = new this.constructor()
+    struct._origin = this._left
+    struct._left = this._left
+    struct._right = this
+    struct._right_origin = this
+    struct._parent = this._parent
+    struct._parentSub = this._parentSub
+    return struct
+  }
+  get _lastId () {
+    return new ID(this._id.user, this._id.clock + this._length - 1)
+  }
+  get _length () {
+    return 1
+  }
+  /**
+   * Splits this struct so that another struct can be inserted in-between.
+   * This must be overwritten if _length > 1
+   * Returns right part after split
+   * - diff === 0 => this
+   * - diff === length => this._right
+   * - otherwise => split _content and return right part of split
+   * (see ItemJSON/ItemString for implementation)
+   */
+  _splitAt (y, diff) {
+    if (diff === 0) {
+      return this
+    }
+    return this._right
+  }
+  _delete (y, createDelete = true) {
+    this._deleted = true
+    y.ds.markDeleted(this._id, this._length)
+    if (createDelete) {
+      let del = new Delete()
+      del._targetID = this._id
+      del._length = this._length
+      del._integrate(y, true)
+    }
+    transactionTypeChanged(y, this._parent, this._parentSub)
+    y._transaction.deletedStructs.add(this)
+  }
+  /**
+   * This is called right before this struct receives any children.
+   * It can be overwritten to apply pending changes before applying remote changes
+   */
+  _beforeChange () {
+    // nop
+  }
+  /*
+   * - Integrate the struct so that other types/structs can see it
+   * - Add this struct to y.os
+   * - Check if this is struct deleted
+   */
+  _integrate (y) {
+    const parent = this._parent
+    const selfID = this._id
+    const userState = selfID === null ? 0 : y.ss.getState(selfID.user)
+    if (selfID === null) {
+      this._id = y.ss.getNextID(this._length)
+    } else if (selfID.user === RootFakeUserID) {
+      // nop
+    } else if (selfID.clock < userState) {
+      // already applied..
+      return []
+    } else if (selfID.clock === userState) {
+      y.ss.setState(selfID.user, userState + this._length)
+    } else {
+      // missing content from user
+      throw new Error('Can not apply yet!')
+    }
+    if (!parent._deleted && !y._transaction.changedTypes.has(parent) && !y._transaction.newTypes.has(parent)) {
+      // this is the first time parent is updated
+      // or this types is new
+      this._parent._beforeChange()
+    }
+    /*
+    # $this has to find a unique position between origin and the next known character
+    # case 1: $origin equals $o.origin: the $creator parameter decides if left or right
+    #         let $OL= [o1,o2,o3,o4], whereby $this is to be inserted between o1 and o4
+    #         o2,o3 and o4 origin is 1 (the position of o2)
+    #         there is the case that $this.creator < o2.creator, but o3.creator < $this.creator
+    #         then o2 knows o3. Since on another client $OL could be [o1,o3,o4] the problem is complex
+    #         therefore $this would be always to the right of o3
+    # case 2: $origin < $o.origin
+    #         if current $this insert_position > $o origin: $this ins
+    #         else $insert_position will not change
+    #         (maybe we encounter case 1 later, then this will be to the right of $o)
+    # case 3: $origin > $o.origin
+    #         $this insert_position is to the left of $o (forever!)
+    */
+    // handle conflicts
+    let o
+    // set o to the first conflicting item
+    if (this._left !== null) {
+      o = this._left._right
+    } else if (this._parentSub !== null) {
+      o = this._parent._map.get(this._parentSub) || null
+    } else {
+      o = this._parent._start
+    }
+    let conflictingItems = new Set()
+    let itemsBeforeOrigin = new Set()
+    // Let c in conflictingItems, b in itemsBeforeOrigin
+    // ***{origin}bbbb{this}{c,b}{c,b}{o}***
+    // Note that conflictingItems is a subset of itemsBeforeOrigin
+    while (o !== null && o !== this._right) {
+      itemsBeforeOrigin.add(o)
+      conflictingItems.add(o)
+      if (this._origin === o._origin) {
+        // case 1
+        if (o._id.user < this._id.user) {
+          this._left = o
+          conflictingItems.clear()
+        }
+      } else if (itemsBeforeOrigin.has(o._origin)) {
+        // case 2
+        if (!conflictingItems.has(o._origin)) {
+          this._left = o
+          conflictingItems.clear()
+        }
+      } else {
+        break
+      }
+      // TODO: try to use right_origin instead.
+      // Then you could basically omit conflictingItems!
+      // Note: you probably can't use right_origin in every case.. only when setting _left
+      o = o._right
+    }
+    // reconnect left/right + update parent map/start if necessary
+    const parentSub = this._parentSub
+    if (this._left === null) {
+      let right
+      if (parentSub !== null) {
+        const pmap = parent._map
+        right = pmap.get(parentSub) || null
+        pmap.set(parentSub, this)
+      } else {
+        right = parent._start
+        parent._start = this
+      }
+      this._right = right
+      if (right !== null) {
+        right._left = this
+      }
+    } else {
+      const left = this._left
+      const right = left._right
+      this._right = right
+      left._right = this
+      if (right !== null) {
+        right._left = this
+      }
+    }
+    if (parent._deleted) {
+      this._delete(y, false)
+    }
+    y.os.put(this)
+    transactionTypeChanged(y, parent, parentSub)
+    if (this._id.user !== RootFakeUserID) {
+      if (y.connector._forwardAppliedStructs || this._id.user === y.userID) {
+        y.connector.broadcastStruct(this)
+      }
+      if (y.persistence !== null) {
+        y.persistence.saveOperations(this)
+      }
+    }
+  }
+  _toBinary (encoder) {
+    encoder.writeUint8(getReference(this.constructor))
+    let info = 0
+    if (this._origin !== null) {
+      info += 0b1 // origin is defined
+    }
+    // TODO: remove
+    /* no longer send _left
+    if (this._left !== this._origin) {
+      info += 0b10 // do not copy origin to left
+    }
+    */
+    if (this._right_origin !== null) {
+      info += 0b100
+    }
+    if (this._parentSub !== null) {
+      info += 0b1000
+    }
+    encoder.writeUint8(info)
+    encoder.writeID(this._id)
+    if (info & 0b1) {
+      encoder.writeID(this._origin._lastId)
+    }
+    // TODO: remove
+    /* see above
+    if (info & 0b10) {
+      encoder.writeID(this._left._lastId)
+    }
+    */
+    if (info & 0b100) {
+      encoder.writeID(this._right_origin._id)
+    }
+    if ((info & 0b101) === 0) {
+      // neither origin nor right is defined
+      encoder.writeID(this._parent._id)
+    }
+    if (info & 0b1000) {
+      encoder.writeVarString(JSON.stringify(this._parentSub))
+    }
+  }
+  _fromBinary (y, decoder) {
+    let missing = []
+    const info = decoder.readUint8()
+    const id = decoder.readID()
+    this._id = id
+    // read origin
+    if (info & 0b1) {
+      // origin != null
+      const originID = decoder.readID()
+      // we have to query for left again because it might have been split/merged..
+      const origin = y.os.getItemCleanEnd(originID)
+      if (origin === null) {
+        missing.push(originID)
+      } else {
+        this._origin = origin
+        this._left = this._origin
+      }
+    }
+    // read right
+    if (info & 0b100) {
+      // right != null
+      const rightID = decoder.readID()
+      // we have to query for right again because it might have been split/merged..
+      const right = y.os.getItemCleanStart(rightID)
+      if (right === null) {
+        missing.push(rightID)
+      } else {
+        this._right = right
+        this._right_origin = right
+      }
+    }
+    // read parent
+    if ((info & 0b101) === 0) {
+      // neither origin nor right is defined
+      const parentID = decoder.readID()
+      // parent does not change, so we don't have to search for it again
+      if (this._parent === null) {
+        const parent = y.os.get(parentID)
+        if (parent === null) {
+          missing.push(parentID)
+        } else {
+          this._parent = parent
+        }
+      }
+    } else if (this._parent === null) {
+      if (this._origin !== null) {
+        this._parent = this._origin._parent
+      } else if (this._right_origin !== null) {
+        this._parent = this._right_origin._parent
+      }
+    }
+    if (info & 0b1000) {
+      // TODO: maybe put this in read parent condition (you can also read parentsub from left/right)
+      this._parentSub = JSON.parse(decoder.readVarString())
+    }
+    if (y.ss.getState(id.user) < id.clock) {
+      missing.push(new ID(id.user, id.clock - 1))
+    }
+    return missing
+  }
+}

src/Struct/ItemJSON.js

@@ -0,0 +1,64 @@
+import { splitHelper, default as Item } from './Item.js'
+import { logID } from '../MessageHandler/messageToString.js'
+
+export default class ItemJSON extends Item {
+  constructor () {
+    super()
+    this._content = null
+  }
+  _copy () {
+    let struct = super._copy()
+    struct._content = this._content
+    return struct
+  }
+  get _length () {
+    return this._content.length
+  }
+  _fromBinary (y, decoder) {
+    let missing = super._fromBinary(y, decoder)
+    let len = decoder.readVarUint()
+    this._content = new Array(len)
+    for (let i = 0; i < len; i++) {
+      const ctnt = decoder.readVarString()
+      let parsed
+      if (ctnt === 'undefined') {
+        parsed = undefined
+      } else {
+        parsed = JSON.parse(ctnt)
+      }
+      this._content[i] = parsed
+    }
+    return missing
+  }
+  _toBinary (encoder) {
+    super._toBinary(encoder)
+    let len = this._content.length
+    encoder.writeVarUint(len)
+    for (let i = 0; i < len; i++) {
+      let encoded
+      let content = this._content[i]
+      if (content === undefined) {
+        encoded = 'undefined'
+      } else {
+        encoded = JSON.stringify(content)
+      }
+      encoder.writeVarString(encoded)
+    }
+  }
+  _logString () {
+    const left = this._left !== null ? this._left._lastId : null
+    const origin = this._origin !== null ? this._origin._lastId : null
+    return `ItemJSON(id:${logID(this._id)},content:${JSON.stringify(this._content)},left:${logID(left)},origin:${logID(origin)},right:${logID(this._right)},parent:${logID(this._parent)},parentSub:${this._parentSub})`
+  }
+  _splitAt (y, diff) {
+    if (diff === 0) {
+      return this
+    } else if (diff >= this._length) {
+      return this._right
+    }
+    let item = new ItemJSON()
+    item._content = this._content.splice(diff)
+    splitHelper(y, this, item, diff)
+    return item
+  }
+}

src/Struct/ItemString.js

@@ -0,0 +1,43 @@
+import { splitHelper, default as Item } from './Item.js'
+import { logID } from '../MessageHandler/messageToString.js'
+
+export default class ItemString extends Item {
+  constructor () {
+    super()
+    this._content = null
+  }
+  _copy () {
+    let struct = super._copy()
+    struct._content = this._content
+    return struct
+  }
+  get _length () {
+    return this._content.length
+  }
+  _fromBinary (y, decoder) {
+    let missing = super._fromBinary(y, decoder)
+    this._content = decoder.readVarString()
+    return missing
+  }
+  _toBinary (encoder) {
+    super._toBinary(encoder)
+    encoder.writeVarString(this._content)
+  }
+  _logString () {
+    const left = this._left !== null ? this._left._lastId : null
+    const origin = this._origin !== null ? this._origin._lastId : null
+    return `ItemJSON(id:${logID(this._id)},content:${JSON.stringify(this._content)},left:${logID(left)},origin:${logID(origin)},right:${logID(this._right)},parent:${logID(this._parent)},parentSub:${this._parentSub})`
+  }
+  _splitAt (y, diff) {
+    if (diff === 0) {
+      return this
+    } else if (diff >= this._length) {
+      return this._right
+    }
+    let item = new ItemString()
+    item._content = this._content.slice(diff)
+    this._content = this._content.slice(0, diff)
+    splitHelper(y, this, item, diff)
+    return item
+  }
+}

src/Struct/Type.js

@@ -0,0 +1,172 @@
+import Item from './Item.js'
+import EventHandler from '../Util/EventHandler.js'
+import ID from '../Util/ID.js'
+
+// restructure children as if they were inserted one after another
+function integrateChildren (y, start) {
+  let right
+  do {
+    right = start._right
+    start._right = null
+    start._right_origin = null
+    start._origin = start._left
+    start._integrate(y)
+    start = right
+  } while (right !== null)
+}
+
+export function getListItemIDByPosition (type, i) {
+  let pos = 0
+  let n = type._start
+  while (n !== null) {
+    if (!n._deleted) {
+      if (pos <= i && i < pos + n._length) {
+        const id = n._id
+        return new ID(id.user, id.clock + i - pos)
+      }
+      pos++
+    }
+    n = n._right
+  }
+}
+
+export default class Type extends Item {
+  constructor () {
+    super()
+    this._map = new Map()
+    this._start = null
+    this._y = null
+    this._eventHandler = new EventHandler()
+    this._deepEventHandler = new EventHandler()
+  }
+  getPathTo (type) {
+    if (type === this) {
+      return []
+    }
+    const path = []
+    const y = this._y
+    while (type._parent !== this && this._parent !== y) {
+      let parent = type._parent
+      if (type._parentSub !== null) {
+        path.push(type._parentSub)
+      } else {
+        // parent is array-ish
+        for (let [i, child] of parent) {
+          if (child === type) {
+            path.push(i)
+            break
+          }
+        }
+      }
+      type = parent
+    }
+    if (this._parent !== this) {
+      throw new Error('The type is not a child of this node')
+    }
+    return path
+  }
+  _callEventHandler (transaction, event) {
+    const changedParentTypes = transaction.changedParentTypes
+    this._eventHandler.callEventListeners(transaction, event)
+    let type = this
+    while (type !== this._y) {
+      let events = changedParentTypes.get(type)
+      if (events === undefined) {
+        events = []
+        changedParentTypes.set(type, events)
+      }
+      events.push(event)
+      type = type._parent
+    }
+  }
+  _copy (undeleteChildren) {
+    let copy = super._copy()
+    let map = new Map()
+    copy._map = map
+    for (let [key, value] of this._map) {
+      if (undeleteChildren.has(value) || !value.deleted) {
+        let _item = value._copy(undeleteChildren)
+        _item._parent = copy
+        map.set(key, value._copy(undeleteChildren))
+      }
+    }
+    let prevUndeleted = null
+    copy._start = null
+    let item = this._start
+    while (item !== null) {
+      if (undeleteChildren.has(item) || !item.deleted) {
+        let _item = item._copy(undeleteChildren)
+        _item._left = prevUndeleted
+        _item._origin = prevUndeleted
+        _item._right = null
+        _item._right_origin = null
+        _item._parent = copy
+        if (prevUndeleted === null) {
+          copy._start = _item
+        } else {
+          prevUndeleted._right = _item
+        }
+        prevUndeleted = _item
+      }
+      item = item._right
+    }
+    return copy
+  }
+  _transact (f) {
+    const y = this._y
+    if (y !== null) {
+      y.transact(f)
+    } else {
+      f(y)
+    }
+  }
+  observe (f) {
+    this._eventHandler.addEventListener(f)
+  }
+  observeDeep (f) {
+    this._deepEventHandler.addEventListener(f)
+  }
+  unobserve (f) {
+    this._eventHandler.removeEventListener(f)
+  }
+  unobserveDeep (f) {
+    this._deepEventHandler.removeEventListener(f)
+  }
+  _integrate (y) {
+    y._transaction.newTypes.add(this)
+    super._integrate(y)
+    this._y = y
+    // when integrating children we must make sure to
+    // integrate start
+    const start = this._start
+    if (start !== null) {
+      this._start = null
+      integrateChildren(y, start)
+    }
+    // integrate map children
+    const map = this._map
+    this._map = new Map()
+    for (let t of map.values()) {
+      // TODO make sure that right elements are deleted!
+      integrateChildren(y, t)
+    }
+  }
+  _delete (y, createDelete) {
+    super._delete(y, createDelete)
+    y._transaction.changedTypes.delete(this)
+    // delete map types
+    for (let value of this._map.values()) {
+      if (value instanceof Item && !value._deleted) {
+        value._delete(y, false)
+      }
+    }
+    // delete array types
+    let t = this._start
+    while (t !== null) {
+      if (!t._deleted) {
+        t._delete(y, false)
+      }
+      t = t._right
+    }
+  }
+}

src/Type/YArray.js

@@ -0,0 +1,222 @@
+import Type from '../Struct/Type.js'
+import ItemJSON from '../Struct/ItemJSON.js'
+import ItemString from '../Struct/ItemString.js'
+import { logID } from '../MessageHandler/messageToString.js'
+import YEvent from '../Util/YEvent.js'
+
+class YArrayEvent extends YEvent {
+  constructor (yarray, remote) {
+    super(yarray)
+    this.remote = remote
+  }
+}
+
+export default class YArray extends Type {
+  _callObserver (transaction, parentSubs, remote) {
+    this._callEventHandler(transaction, new YArrayEvent(this, remote))
+  }
+  get (pos) {
+    let n = this._start
+    while (n !== null) {
+      if (!n._deleted) {
+        if (pos < n._length) {
+          if (n.constructor === ItemJSON || n.constructor === ItemString) {
+            return n._content[pos]
+          } else {
+            return n
+          }
+        }
+        pos -= n._length
+      }
+      n = n._right
+    }
+  }
+  toArray () {
+    return this.map(c => c)
+  }
+  toJSON () {
+    return this.map(c => {
+      if (c instanceof Type) {
+        if (c.toJSON !== null) {
+          return c.toJSON()
+        } else {
+          return c.toString()
+        }
+      }
+      return c
+    })
+  }
+  map (f) {
+    const res = []
+    this.forEach((c, i) => {
+      res.push(f(c, i, this))
+    })
+    return res
+  }
+  forEach (f) {
+    let pos = 0
+    let n = this._start
+    while (n !== null) {
+      if (!n._deleted) {
+        if (n instanceof Type) {
+          f(n, pos++, this)
+        } else {
+          const content = n._content
+          const contentLen = content.length
+          for (let i = 0; i < contentLen; i++) {
+            pos++
+            f(content[i], pos, this)
+          }
+        }
+      }
+      n = n._right
+    }
+  }
+  get length () {
+    let length = 0
+    let n = this._start
+    while (n !== null) {
+      if (!n._deleted) {
+        length += n._length
+      }
+      n = n._right
+    }
+    return length
+  }
+  [Symbol.iterator] () {
+    return {
+      next: function () {
+        while (this._item !== null && (this._item._deleted || this._item._length <= this._itemElement)) {
+          // item is deleted or itemElement does not exist (is deleted)
+          this._item = this._item._right
+          this._itemElement = 0
+        }
+        if (this._item === null) {
+          return {
+            done: true
+          }
+        }
+        let content
+        if (this._item instanceof Type) {
+          content = this._item
+        } else {
+          content = this._item._content[this._itemElement++]
+        }
+        return {
+          value: [this._count, content],
+          done: false
+        }
+      },
+      _item: this._start,
+      _itemElement: 0,
+      _count: 0
+    }
+  }
+  delete (pos, length = 1) {
+    this._y.transact(() => {
+      let item = this._start
+      let count = 0
+      while (item !== null && length > 0) {
+        if (!item._deleted) {
+          if (count <= pos && pos < count + item._length) {
+            const diffDel = pos - count
+            item = item._splitAt(this._y, diffDel)
+            item._splitAt(this._y, length)
+            length -= item._length
+            item._delete(this._y)
+            count += diffDel
+          } else {
+            count += item._length
+          }
+        }
+        item = item._right
+      }
+    })
+    if (length > 0) {
+      throw new Error('Delete exceeds the range of the YArray')
+    }
+  }
+  insertAfter (left, content) {
+    this._transact(y => {
+      let right
+      if (left === null) {
+        right = this._start
+      } else {
+        right = left._right
+      }
+      let prevJsonIns = null
+      for (let i = 0; i < content.length; i++) {
+        let c = content[i]
+        if (typeof c === 'function') {
+          c = new c() // eslint-disable-line new-cap
+        }
+        if (c instanceof Type) {
+          if (prevJsonIns !== null) {
+            if (y !== null) {
+              prevJsonIns._integrate(y)
+            }
+            left = prevJsonIns
+            prevJsonIns = null
+          }
+          c._origin = left
+          c._left = left
+          c._right = right
+          c._right_origin = right
+          c._parent = this
+          if (y !== null) {
+            c._integrate(y)
+          } else if (left === null) {
+            this._start = c
+          } else {
+            left._right = c
+          }
+          left = c
+        } else {
+          if (prevJsonIns === null) {
+            prevJsonIns = new ItemJSON()
+            prevJsonIns._origin = left
+            prevJsonIns._left = left
+            prevJsonIns._right = right
+            prevJsonIns._right_origin = right
+            prevJsonIns._parent = this
+            prevJsonIns._content = []
+          }
+          prevJsonIns._content.push(c)
+        }
+      }
+      if (prevJsonIns !== null && y !== null) {
+        prevJsonIns._integrate(y)
+      }
+    })
+  }
+  insert (pos, content) {
+    let left = null
+    let right = this._start
+    let count = 0
+    const y = this._y
+    while (right !== null) {
+      const rightLen = right._deleted ? 0 : (right._length - 1)
+      if (count <= pos && pos <= count + rightLen) {
+        const splitDiff = pos - count
+        right = right._splitAt(y, splitDiff)
+        left = right._left
+        count += splitDiff
+        break
+      }
+      if (!right._deleted) {
+        count += right._length
+      }
+      left = right
+      right = right._right
+    }
+    if (pos > count) {
+      throw new Error('Position exceeds array range!')
+    }
+    this.insertAfter(left, content)
+  }
+  _logString () {
+    const left = this._left !== null ? this._left._lastId : null
+    const origin = this._origin !== null ? this._origin._lastId : null
+    return `YArray(id:${logID(this._id)},start:${logID(this._start)},left:${logID(left)},origin:${logID(origin)},right:${logID(this._right)},parent:${logID(this._parent)},parentSub:${this._parentSub})`
+  }
+}

src/Type/YMap.js

@@ -0,0 +1,114 @@
+import Type from '../Struct/Type.js'
+import Item from '../Struct/Item.js'
+import ItemJSON from '../Struct/ItemJSON.js'
+import { logID } from '../MessageHandler/messageToString.js'
+import YEvent from '../Util/YEvent.js'
+
+class YMapEvent extends YEvent {
+  constructor (ymap, subs, remote) {
+    super(ymap)
+    this.keysChanged = subs
+    this.remote = remote
+  }
+}
+
+export default class YMap extends Type {
+  _callObserver (transaction, parentSubs, remote) {
+    this._callEventHandler(transaction, new YMapEvent(this, parentSubs, remote))
+  }
+  toJSON () {
+    const map = {}
+    for (let [key, item] of this._map) {
+      if (!item._deleted) {
+        let res
+        if (item instanceof Type) {
+          if (item.toJSON !== undefined) {
+            res = item.toJSON()
+          } else {
+            res = item.toString()
+          }
+        } else {
+          res = item._content[0]
+        }
+        map[key] = res
+      }
+    }
+    return map
+  }
+  keys () {
+    let keys = []
+    for (let [key, value] of this._map) {
+      if (!value._deleted) {
+        keys.push(key)
+      }
+    }
+    return keys
+  }
+  delete (key) {
+    this._transact((y) => {
+      let c = this._map.get(key)
+      if (y !== null && c !== undefined) {
+        c._delete(y)
+      }
+    })
+  }
+  set (key, value) {
+    this._transact(y => {
+      const old = this._map.get(key) || null
+      if (old !== null) {
+        if (old instanceof ItemJSON && old._content[0] === value) {
+          // Trying to overwrite with same value
+          // break here
+          return value
+        }
+        if (y !== null) {
+          old._delete(y)
+        }
+      }
+      let v
+      if (typeof value === 'function') {
+        v = new value() // eslint-disable-line new-cap
+        value = v
+      } else if (value instanceof Item) {
+        v = value
+      } else {
+        v = new ItemJSON()
+        v._content = [value]
+      }
+      v._right = old
+      v._right_origin = old
+      v._parent = this
+      v._parentSub = key
+      if (y !== null) {
+        v._integrate(y)
+      } else {
+        this._map.set(key, v)
+      }
+    })
+    return value
+  }
+  get (key) {
+    let v = this._map.get(key)
+    if (v === undefined || v._deleted) {
+      return undefined
+    }
+    if (v instanceof Type) {
+      return v
+    } else {
+      return v._content[v._content.length - 1]
+    }
+  }
+  has (key) {
+    let v = this._map.get(key)
+    if (v === undefined || v._deleted) {
+      return false
+    } else {
+      return true
+    }
+  }
+  _logString () {
+    const left = this._left !== null ? this._left._lastId : null
+    const origin = this._origin !== null ? this._origin._lastId : null
+    return `YMap(id:${logID(this._id)},mapSize:${this._map.size},left:${logID(left)},origin:${logID(origin)},right:${logID(this._right)},parent:${logID(this._parent)},parentSub:${this._parentSub})`
+  }
+}

src/Type/YText.js

@@ -0,0 +1,67 @@
+import ItemString from '../Struct/ItemString.js'
+import YArray from './YArray.js'
+import { logID } from '../MessageHandler/messageToString.js'
+
+export default class YText extends YArray {
+  constructor (string) {
+    super()
+    if (typeof string === 'string') {
+      const start = new ItemString()
+      start._parent = this
+      start._content = string
+      this._start = start
+    }
+  }
+  toString () {
+    const strBuilder = []
+    let n = this._start
+    while (n !== null) {
+      if (!n._deleted) {
+        strBuilder.push(n._content)
+      }
+      n = n._right
+    }
+    return strBuilder.join('')
+  }
+  insert (pos, text) {
+    this._transact(y => {
+      let left = null
+      let right = this._start
+      let count = 0
+      while (right !== null) {
+        if (count <= pos && pos < count + right._length) {
+          const splitDiff = pos - count
+          right = right._splitAt(this._y, pos - count)
+          left = right._left
+          count += splitDiff
+          break
+        }
+        count += right._length
+        left = right
+        right = right._right
+      }
+      if (pos > count) {
+        throw new Error('Position exceeds array range!')
+      }
+      let item = new ItemString()
+      item._origin = left
+      item._left = left
+      item._right = right
+      item._right_origin = right
+      item._parent = this
+      item._content = text
+      if (y !== null) {
+        item._integrate(this._y)
+      } else if (left === null) {
+        this._start = item
+      } else {
+        left._right = item
+      }
+    })
+  }
+  _logString () {
+    const left = this._left !== null ? this._left._lastId : null
+    const origin = this._origin !== null ? this._origin._lastId : null
+    return `YText(id:${logID(this._id)},start:${logID(this._start)},left:${logID(left)},origin:${logID(origin)},right:${logID(this._right)},parent:${logID(this._parent)},parentSub:${this._parentSub})`
+  }
+}

src/Type/y-xml/YXmlElement.js

@@ -0,0 +1,131 @@
+// import diff from 'fast-diff'
+import { defaultDomFilter } from './utils.js'
+
+import YMap from '../YMap.js'
+import YXmlFragment from './YXmlFragment.js'
+
+export default class YXmlElement extends YXmlFragment {
+  constructor (arg1, arg2) {
+    super()
+    this.nodeName = null
+    this._scrollElement = null
+    if (typeof arg1 === 'string') {
+      this.nodeName = arg1.toUpperCase()
+    } else if (arg1 != null && arg1.nodeType != null && arg1.nodeType === arg1.ELEMENT_NODE) {
+      this.nodeName = arg1.nodeName
+      this._setDom(arg1)
+    } else {
+      this.nodeName = 'UNDEFINED'
+    }
+    if (typeof arg2 === 'function') {
+      this._domFilter = arg2
+    }
+  }
+  _copy (undeleteChildren) {
+    let struct = super._copy(undeleteChildren)
+    struct.nodeName = this.nodeName
+    return struct
+  }
+  _setDom (dom) {
+    if (this._dom != null) {
+      throw new Error('Only call this method if you know what you are doing ;)')
+    } else if (dom._yxml != null) { // TODO do i need to check this? - no.. but for dev purps..
+      throw new Error('Already bound to an YXml type')
+    } else {
+      this._dom = dom
+      dom._yxml = this
+      // tag is already set in constructor
+      // set attributes
+      let attrNames = []
+      for (let i = 0; i < dom.attributes.length; i++) {
+        attrNames.push(dom.attributes[i].name)
+      }
+      attrNames = this._domFilter(dom, attrNames)
+      for (let i = 0; i < attrNames.length; i++) {
+        let attrName = attrNames[i]
+        let attrValue = dom.getAttribute(attrName)
+        this.setAttribute(attrName, attrValue)
+      }
+      this.insertDomElements(0, Array.prototype.slice.call(dom.childNodes))
+      this._bindToDom(dom)
+      return dom
+    }
+  }
+  _fromBinary (y, decoder) {
+    const missing = super._fromBinary(y, decoder)
+    this.nodeName = decoder.readVarString()
+    return missing
+  }
+  _toBinary (encoder) {
+    super._toBinary(encoder)
+    encoder.writeVarString(this.nodeName)
+  }
+  _integrate (y) {
+    if (this.nodeName === null) {
+      throw new Error('nodeName must be defined!')
+    }
+    if (this._domFilter === defaultDomFilter && this._parent instanceof YXmlFragment) {
+      this._domFilter = this._parent._domFilter
+    }
+    super._integrate(y)
+  }
+  /**
+   * Returns the string representation of the XML document.
+   * The attributes are ordered by attribute-name, so you can easily use this
+   * method to compare YXmlElements
+   */
+  toString () {
+    const attrs = this.getAttributes()
+    const stringBuilder = []
+    const keys = []
+    for (let key in attrs) {
+      keys.push(key)
+    }
+    keys.sort()
+    const keysLen = keys.length
+    for (let i = 0; i < keysLen; i++) {
+      const key = keys[i]
+      stringBuilder.push(key + '="' + attrs[key] + '"')
+    }
+    const nodeName = this.nodeName.toLocaleLowerCase()
+    const attrsString = stringBuilder.length > 0 ? ' ' + stringBuilder.join(' ') : ''
+    return `<${nodeName}${attrsString}>${super.toString()}</${nodeName}>`
+  }
+  removeAttribute () {
+    return YMap.prototype.delete.apply(this, arguments)
+  }
+
+  setAttribute () {
+    return YMap.prototype.set.apply(this, arguments)
+  }
+
+  getAttribute () {
+    return YMap.prototype.get.apply(this, arguments)
+  }
+
+  getAttributes () {
+    const obj = {}
+    for (let [key, value] of this._map) {
+      obj[key] = value._content[0]
+    }
+    return obj
+  }
+  getDom (_document) {
+    _document = _document || document
+    let dom = this._dom
+    if (dom == null) {
+      dom = _document.createElement(this.nodeName)
+      this._dom = dom
+      dom._yxml = this
+      let attrs = this.getAttributes()
+      for (let key in attrs) {
+        dom.setAttribute(key, attrs[key])
+      }
+      this.forEach(yxml => {
+        dom.appendChild(yxml.getDom(_document))
+      })
+      this._bindToDom(dom)
+    }
+    return dom
+  }
+}

src/Type/y-xml/YXmlEvent.js

@@ -0,0 +1,17 @@
+import YEvent from '../../Util/YEvent.js'
+
+export default class YXmlEvent extends YEvent {
+  constructor (target, subs, remote) {
+    super(target)
+    this.childListChanged = false
+    this.attributesChanged = new Set()
+    this.remote = remote
+    subs.forEach((sub) => {
+      if (sub === null) {
+        this.childListChanged = true
+      } else {
+        this.attributesChanged.add(sub)
+      }
+    })
+  }
+}

src/Type/y-xml/YXmlFragment.js

@@ -0,0 +1,279 @@
+/* global MutationObserver */
+
+import { defaultDomFilter, applyChangesFromDom, reflectChangesOnDom } from './utils.js'
+import { beforeTransactionSelectionFixer, afterTransactionSelectionFixer } from './selection.js'
+
+import YArray from '../YArray.js'
+import YXmlText from './YXmlText.js'
+import YXmlEvent from './YXmlEvent.js'
+import { logID } from '../../MessageHandler/messageToString.js'
+import diff from 'fast-diff'
+
+function domToYXml (parent, doms) {
+  const types = []
+  doms.forEach(d => {
+    if (d._yxml != null && d._yxml !== false) {
+      d._yxml._unbindFromDom()
+    }
+    if (parent._domFilter(d, []) !== null) {
+      let type
+      if (d.nodeType === d.TEXT_NODE) {
+        type = new YXmlText(d)
+      } else if (d.nodeType === d.ELEMENT_NODE) {
+        type = new YXmlFragment._YXmlElement(d, parent._domFilter)
+      } else {
+        throw new Error('Unsupported node!')
+      }
+      type.enableSmartScrolling(parent._scrollElement)
+      types.push(type)
+    } else {
+      d._yxml = false
+    }
+  })
+  return types
+}
+
+class YXmlTreeWalker {
+  constructor (root, f) {
+    this._filter = f || (() => true)
+    this._root = root
+    this._currentNode = root
+    this._firstCall = true
+  }
+  [Symbol.iterator] () {
+    return this
+  }
+  next () {
+    let n = this._currentNode
+    if (this._firstCall) {
+      this._firstCall = false
+      if (!n._deleted && this._filter(n)) {
+        return { value: n, done: false }
+      }
+    }
+    do {
+      if (!n._deleted && n.constructor === YXmlFragment._YXmlElement && n._start !== null) {
+        // walk down in the tree
+        n = n._start
+      } else {
+        // walk right or up in the tree
+        while (n !== this._root) {
+          if (n._right !== null) {
+            n = n._right
+            break
+          }
+          n = n._parent
+        }
+        if (n === this._root) {
+          n = null
+        }
+      }
+      if (n === this._root) {
+        break
+      }
+    } while (n !== null && (n._deleted || !this._filter(n)))
+    this._currentNode = n
+    if (n === null) {
+      return { done: true }
+    } else {
+      return { value: n, done: false }
+    }
+  }
+}
+
+export default class YXmlFragment extends YArray {
+  constructor () {
+    super()
+    this._dom = null
+    this._domFilter = defaultDomFilter
+    this._domObserver = null
+    // this function makes sure that either the
+    // dom event is executed, or the yjs observer is executed
+    var token = true
+    this._mutualExclude = f => {
+      if (token) {
+        token = false
+        try {
+          f()
+        } catch (e) {
+          console.error(e)
+        }
+        this._domObserver.takeRecords()
+        token = true
+      }
+    }
+  }
+  createTreeWalker (filter) {
+    return new YXmlTreeWalker(this, filter)
+  }
+  /**
+   * Retrieve first element that matches *query*
+   * Similar to DOM's querySelector, but only accepts a subset of its queries
+   *
+   * Query support:
+   *   - tagname
+   * TODO:
+   *   - id
+   *   - attribute
+   */
+  querySelector (query) {
+    query = query.toUpperCase()
+    const iterator = new YXmlTreeWalker(this, element => element.nodeName === query)
+    const next = iterator.next()
+    if (next.done) {
+      return null
+    } else {
+      return next.value
+    }
+  }
+  querySelectorAll (query) {
+    query = query.toUpperCase()
+    return Array.from(new YXmlTreeWalker(this, element => element.nodeName === query))
+  }
+  enableSmartScrolling (scrollElement) {
+    this._scrollElement = scrollElement
+    this.forEach(xml => {
+      xml.enableSmartScrolling(scrollElement)
+    })
+  }
+  setDomFilter (f) {
+    this._domFilter = f
+    this.forEach(xml => {
+      xml.setDomFilter(f)
+    })
+  }
+  _callObserver (transaction, parentSubs, remote) {
+    this._callEventHandler(transaction, new YXmlEvent(this, parentSubs, remote))
+  }
+  toString () {
+    return this.map(xml => xml.toString()).join('')
+  }
+  _delete (y, createDelete) {
+    this._unbindFromDom()
+    super._delete(y, createDelete)
+  }
+  _unbindFromDom () {
+    if (this._domObserver != null) {
+      this._domObserver.disconnect()
+      this._domObserver = null
+    }
+    if (this._dom != null) {
+      this._dom._yxml = null
+      this._dom = null
+    }
+  }
+  insertDomElementsAfter (prev, doms) {
+    const types = domToYXml(this, doms)
+    this.insertAfter(prev, types)
+    return types
+  }
+  insertDomElements (pos, doms) {
+    const types = domToYXml(this, doms)
+    this.insert(pos, types)
+    return types
+  }
+  getDom () {
+    return this._dom
+  }
+  bindToDom (dom) {
+    if (this._dom != null) {
+      this._unbindFromDom()
+    }
+    if (dom._yxml != null) {
+      dom._yxml._unbindFromDom()
+    }
+    if (MutationObserver == null) {
+      throw new Error('Not able to bind to a DOM element, because MutationObserver is not available!')
+    }
+    dom.innerHTML = ''
+    this._dom = dom
+    dom._yxml = this
+    this.forEach(t => {
+      dom.insertBefore(t.getDom(), null)
+    })
+    this._bindToDom(dom)
+  }
+  // binds to a dom element
+  // Only call if dom and YXml are isomorph
+  _bindToDom (dom) {
+    if (this._parent === null || this._parent._dom != null || typeof MutationObserver === 'undefined') {
+      // only bind if parent did not already bind
+      return
+    }
+    this._y.on('beforeTransaction', () => {
+      this._domObserverListener(this._domObserver.takeRecords())
+    })
+    this._y.on('beforeTransaction', beforeTransactionSelectionFixer)
+    this._y.on('afterTransaction', afterTransactionSelectionFixer)
+    // Apply Y.Xml events to dom
+    this.observeDeep(reflectChangesOnDom.bind(this))
+    // Apply Dom changes on Y.Xml
+    this._domObserverListener = mutations => {
+      this._mutualExclude(() => {
+        this._y.transact(() => {
+          let diffChildren = new Set()
+          mutations.forEach(mutation => {
+            const dom = mutation.target
+            const yxml = dom._yxml
+            if (yxml == null) {
+              // dom element is filtered
+              return
+            }
+            switch (mutation.type) {
+              case 'characterData':
+                var diffs = diff(yxml.toString(), dom.nodeValue)
+                var pos = 0
+                for (var i = 0; i < diffs.length; i++) {
+                  var d = diffs[i]
+                  if (d[0] === 0) { // EQUAL
+                    pos += d[1].length
+                  } else if (d[0] === -1) { // DELETE
+                    yxml.delete(pos, d[1].length)
+                  } else { // INSERT
+                    yxml.insert(pos, d[1])
+                    pos += d[1].length
+                  }
+                }
+                break
+              case 'attributes':
+                let name = mutation.attributeName
+                // check if filter accepts attribute
+                if (this._domFilter(dom, [name]).length > 0 && this.constructor !== YXmlFragment) {
+                  var val = dom.getAttribute(name)
+                  if (yxml.getAttribute(name) !== val) {
+                    if (val == null) {
+                      yxml.removeAttribute(name)
+                    } else {
+                      yxml.setAttribute(name, val)
+                    }
+                  }
+                }
+                break
+              case 'childList':
+                diffChildren.add(mutation.target)
+                break
+            }
+          })
+          for (let dom of diffChildren) {
+            if (dom._yxml != null && dom._yxml !== false) {
+              applyChangesFromDom(dom)
+            }
+          }
+        })
+      })
+    }
+    this._domObserver = new MutationObserver(this._domObserverListener)
+    this._domObserver.observe(dom, {
+      childList: true,
+      attributes: true,
+      characterData: true,
+      subtree: true
+    })
+    return dom
+  }
+  _logString () {
+    const left = this._left !== null ? this._left._lastId : null
+    const origin = this._origin !== null ? this._origin._lastId : null
+    return `YXml(id:${logID(this._id)},left:${logID(left)},origin:${logID(origin)},right:${this._right},parent:${logID(this._parent)},parentSub:${this._parentSub})`
+  }
+}

src/Type/y-xml/YXmlText.js

@@ -0,0 +1,93 @@
+import YText from '../YText.js'
+
+export default class YXmlText extends YText {
+  constructor (arg1) {
+    let dom = null
+    let initialText = null
+    if (arg1 != null) {
+      if (arg1.nodeType != null && arg1.nodeType === arg1.TEXT_NODE) {
+        dom = arg1
+        initialText = dom.nodeValue
+      } else if (typeof arg1 === 'string') {
+        initialText = arg1
+      }
+    }
+    super(initialText)
+    this._dom = null
+    this._domObserver = null
+    this._domObserverListener = null
+    this._scrollElement = null
+    if (dom !== null) {
+      this._setDom(arg1)
+    }
+    /*
+    var token = true
+    this._mutualExclude = f => {
+      if (token) {
+        token = false
+        try {
+          f()
+        } catch (e) {
+          console.error(e)
+        }
+        this._domObserver.takeRecords()
+        token = true
+      }
+    }
+    this.observe(event => {
+      if (this._dom != null) {
+        const dom = this._dom
+        this._mutualExclude(() => {
+          let anchorViewPosition = getAnchorViewPosition(this._scrollElement)
+          let anchorViewFix
+          if (anchorViewPosition !== null && (anchorViewPosition.anchor !== null || getBoundingClientRect(this._dom).top <= 0)) {
+            anchorViewFix = anchorViewPosition
+          } else {
+            anchorViewFix = null
+          }
+          dom.nodeValue = this.toString()
+          fixScrollPosition(this._scrollElement, anchorViewFix)
+        })
+      }
+    })
+    */
+  }
+  setDomFilter () {}
+  enableSmartScrolling (scrollElement) {
+    this._scrollElement = scrollElement
+  }
+  _setDom (dom) {
+    if (this._dom != null) {
+      this._unbindFromDom()
+    }
+    if (dom._yxml != null) {
+      dom._yxml._unbindFromDom()
+    }
+    // set marker
+    this._dom = dom
+    dom._yxml = this
+  }
+  getDom (_document) {
+    _document = _document || document
+    if (this._dom === null) {
+      const dom = _document.createTextNode(this.toString())
+      this._setDom(dom)
+      return dom
+    }
+    return this._dom
+  }
+  _delete (y, createDelete) {
+    this._unbindFromDom()
+    super._delete(y, createDelete)
+  }
+  _unbindFromDom () {
+    if (this._domObserver != null) {
+      this._domObserver.disconnect()
+      this._domObserver = null
+    }
+    if (this._dom != null) {
+      this._dom._yxml = null
+      this._dom = null
+    }
+  }
+}

src/Type/y-xml/selection.js

@@ -0,0 +1,73 @@
+/* globals getSelection */
+
+import { getRelativePosition, fromRelativePosition } from '../../Util/relativePosition.js'
+
+let browserSelection = null
+let relativeSelection = null
+
+export let beforeTransactionSelectionFixer
+if (typeof getSelection !== 'undefined') {
+  beforeTransactionSelectionFixer = function _beforeTransactionSelectionFixer (y, transaction, remote) {
+    if (!remote) {
+      return
+    }
+    relativeSelection = { from: null, to: null, fromY: null, toY: null }
+    browserSelection = getSelection()
+    const anchorNode = browserSelection.anchorNode
+    if (anchorNode !== null && anchorNode._yxml != null) {
+      const yxml = anchorNode._yxml
+      relativeSelection.from = getRelativePosition(yxml, browserSelection.anchorOffset)
+      relativeSelection.fromY = yxml._y
+    }
+    const focusNode = browserSelection.focusNode
+    if (focusNode !== null && focusNode._yxml != null) {
+      const yxml = focusNode._yxml
+      relativeSelection.to = getRelativePosition(yxml, browserSelection.focusOffset)
+      relativeSelection.toY = yxml._y
+    }
+  }
+} else {
+  beforeTransactionSelectionFixer = function _fakeBeforeTransactionSelectionFixer () {}
+}
+
+export function afterTransactionSelectionFixer (y, transaction, remote) {
+  if (relativeSelection === null || !remote) {
+    return
+  }
+  const to = relativeSelection.to
+  const from = relativeSelection.from
+  const fromY = relativeSelection.fromY
+  const toY = relativeSelection.toY
+  let shouldUpdate = false
+  let anchorNode = browserSelection.anchorNode
+  let anchorOffset = browserSelection.anchorOffset
+  let focusNode = browserSelection.focusNode
+  let focusOffset = browserSelection.focusOffset
+  if (from !== null) {
+    let sel = fromRelativePosition(fromY, from)
+    if (sel !== null) {
+      shouldUpdate = true
+      anchorNode = sel.type.getDom()
+      anchorOffset = sel.offset
+    }
+  }
+  if (to !== null) {
+    let sel = fromRelativePosition(toY, to)
+    if (sel !== null) {
+      focusNode = sel.type.getDom()
+      focusOffset = sel.offset
+      shouldUpdate = true
+    }
+  }
+  if (shouldUpdate) {
+    browserSelection.setBaseAndExtent(
+      anchorNode,
+      anchorOffset,
+      focusNode,
+      focusOffset
+    )
+  }
+  // delete, so the objects can be gc'd
+  relativeSelection = null
+  browserSelection = null
+}

src/Type/y-xml/utils.js

@@ -0,0 +1,252 @@
+import YXmlText from './YXmlText.js'
+
+export function defaultDomFilter (node, attributes) {
+  return attributes
+}
+
+export function getAnchorViewPosition (scrollElement) {
+  if (scrollElement == null) {
+    return null
+  }
+  let anchor = document.getSelection().anchorNode
+  if (anchor != null) {
+    let top = getBoundingClientRect(anchor).top
+    if (top >= 0 && top <= document.documentElement.clientHeight) {
+      return {
+        anchor: anchor,
+        top: top
+      }
+    }
+  }
+  return {
+    anchor: null,
+    scrollTop: scrollElement.scrollTop,
+    scrollHeight: scrollElement.scrollHeight
+  }
+}
+
+// get BoundingClientRect that works on text nodes
+export function getBoundingClientRect (element) {
+  if (element.getBoundingClientRect != null) {
+    // is element node
+    return element.getBoundingClientRect()
+  } else {
+    // is text node
+    if (element.parentNode == null) {
+      // range requires that text nodes have a parent
+      let span = document.createElement('span')
+      span.appendChild(element)
+    }
+    let range = document.createRange()
+    range.selectNode(element)
+    return range.getBoundingClientRect()
+  }
+}
+
+export function fixScrollPosition (scrollElement, fix) {
+  if (scrollElement !== null && fix !== null) {
+    if (fix.anchor === null) {
+      if (scrollElement.scrollTop === fix.scrollTop) {
+        scrollElement.scrollTop = scrollElement.scrollHeight - fix.scrollHeight
+      }
+    } else {
+      scrollElement.scrollTop = getBoundingClientRect(fix.anchor).top - fix.top
+    }
+  }
+}
+
+function iterateUntilUndeleted (item) {
+  while (item !== null && item._deleted) {
+    item = item._right
+  }
+  return item
+}
+
+function _insertNodeHelper (yxml, prevExpectedNode, child) {
+  let insertedNodes = yxml.insertDomElementsAfter(prevExpectedNode, [child])
+  if (insertedNodes.length > 0) {
+    return insertedNodes[0]
+  } else {
+    return prevExpectedNode
+  }
+}
+
+/*
+ * 1. Check if any of the nodes was deleted
+ * 2. Iterate over the children.
+ *    2.1 If a node exists without _yxml property, insert a new node
+ *    2.2 If _contents.length < dom.childNodes.length, fill the
+ *        rest of _content with childNodes
+ *    2.3 If a node was moved, delete it and
+ *       recreate a new yxml element that is bound to that node.
+ *       You can detect that a node was moved because expectedId
+ *       !== actualId in the list
+ */
+export function applyChangesFromDom (dom) {
+  const yxml = dom._yxml
+  const y = yxml._y
+  let knownChildren =
+    new Set(
+      Array.prototype.map.call(dom.childNodes, child => child._yxml)
+      .filter(id => id !== undefined)
+    )
+  // 1. Check if any of the nodes was deleted
+  yxml.forEach(function (childType, i) {
+    if (!knownChildren.has(childType)) {
+      childType._delete(y)
+    }
+  })
+  // 2. iterate
+  let childNodes = dom.childNodes
+  let len = childNodes.length
+  let prevExpectedNode = null
+  let expectedNode = iterateUntilUndeleted(yxml._start)
+  for (let domCnt = 0; domCnt < len; domCnt++) {
+    const child = childNodes[domCnt]
+    const childYXml = child._yxml
+    if (childYXml != null) {
+      if (childYXml === false) {
+        // should be ignored or is going to be deleted
+        continue
+      }
+      if (expectedNode !== null) {
+        if (expectedNode !== childYXml) {
+          // 2.3 Not expected node
+          if (childYXml._parent !== this) {
+            // element is going to be deleted by its previous parent
+            child._yxml = null
+          } else {
+            childYXml._delete(y)
+          }
+          prevExpectedNode = _insertNodeHelper(yxml, prevExpectedNode, child)
+        } else {
+          prevExpectedNode = expectedNode
+          expectedNode = iterateUntilUndeleted(expectedNode._right)
+        }
+        // if this is the expected node id, just continue
+      } else {
+        // 2.2 fill _conten with child nodes
+        prevExpectedNode = _insertNodeHelper(yxml, prevExpectedNode, child)
+      }
+    } else {
+      // 2.1 A new node was found
+      prevExpectedNode = _insertNodeHelper(yxml, prevExpectedNode, child)
+    }
+  }
+}
+
+export function reflectChangesOnDom (events) {
+  // Make sure that no filtered attributes are applied to the structure
+  // if they were, delete them
+  /*
+  events.forEach(event => {
+    const target = event.target
+    if (event.attributesChanged === undefined) {
+      // event.target is Y.XmlText
+      return
+    }
+    const keys = this._domFilter(target.nodeName, Array.from(event.attributesChanged))
+    if (keys === null) {
+      target._delete()
+    } else {
+      const removeKeys = new Set() // is a copy of event.attributesChanged
+      event.attributesChanged.forEach(key => { removeKeys.add(key) })
+      keys.forEach(key => {
+        // remove all accepted keys from removeKeys
+        removeKeys.delete(key)
+      })
+      // remove the filtered attribute
+      removeKeys.forEach(key => {
+        target.removeAttribute(key)
+      })
+    }
+  })
+  */
+  this._mutualExclude(() => {
+    events.forEach(event => {
+      const yxml = event.target
+      const dom = yxml._dom
+      if (dom != null) {
+        // TODO: do this once before applying stuff
+        // let anchorViewPosition = getAnchorViewPosition(yxml._scrollElement)
+        if (yxml.constructor === YXmlText) {
+          yxml._dom.nodeValue = yxml.toString()
+        } else {
+          // update attributes
+          event.attributesChanged.forEach(attributeName => {
+            const value = yxml.getAttribute(attributeName)
+            if (value === undefined) {
+              dom.removeAttribute(attributeName)
+            } else {
+              dom.setAttribute(attributeName, value)
+            }
+          })
+          if (event.childListChanged) {
+            // create fragment of undeleted nodes
+            const fragment = document.createDocumentFragment()
+            yxml.forEach(function (t) {
+              fragment.append(t.getDom())
+            })
+            // remove remainding nodes
+            let lastChild = dom.lastChild
+            while (lastChild !== null) {
+              dom.removeChild(lastChild)
+              lastChild = dom.lastChild
+            }
+            // insert fragment of undeleted nodes
+            dom.append(fragment)
+          }
+        }
+        /* TODO: smartscrolling
+        .. else if (event.type === 'childInserted' || event.type === 'insert') {
+          let nodes = event.values
+          for (let i = nodes.length - 1; i >= 0; i--) {
+            let node = nodes[i]
+            node.setDomFilter(yxml._domFilter)
+            node.enableSmartScrolling(yxml._scrollElement)
+            let dom = node.getDom()
+            let fixPosition = null
+            let nextDom = null
+            if (yxml._content.length > event.index + i + 1) {
+              nextDom = yxml.get(event.index + i + 1).getDom()
+            }
+            yxml._dom.insertBefore(dom, nextDom)
+            if (anchorViewPosition === null) {
+              // nop
+            } else if (anchorViewPosition.anchor !== null) {
+              // no scrolling when current selection
+              if (!dom.contains(anchorViewPosition.anchor) && !anchorViewPosition.anchor.contains(dom)) {
+                fixPosition = anchorViewPosition
+              }
+            } else if (getBoundingClientRect(dom).top <= 0) {
+              // adjust scrolling if modified element is out of view,
+              // there is no anchor element, and the browser did not adjust scrollTop (this is checked later)
+              fixPosition = anchorViewPosition
+            }
+            fixScrollPosition(yxml._scrollElement, fixPosition)
+          }
+        } else if (event.type === 'childRemoved' || event.type === 'delete') {
+          for (let i = event.values.length - 1; i >= 0; i--) {
+            let dom = event.values[i]._dom
+            let fixPosition = null
+            if (anchorViewPosition === null) {
+              // nop
+            } else if (anchorViewPosition.anchor !== null) {
+              // no scrolling when current selection
+              if (!dom.contains(anchorViewPosition.anchor) && !anchorViewPosition.anchor.contains(dom)) {
+                fixPosition = anchorViewPosition
+              }
+            } else if (getBoundingClientRect(dom).top <= 0) {
+              // adjust scrolling if modified element is out of view,
+              // there is no anchor element, and the browser did not adjust scrollTop (this is checked later)
+              fixPosition = anchorViewPosition
+            }
+            dom.remove()
+            fixScrollPosition(yxml._scrollElement, fixPosition)
+          }
+        }
+        */
+      }
+    })
+  })
+}

src/Type/y-xml/y-xml.js

@@ -0,0 +1,9 @@
+
+import YXmlFragment from './YXmlFragment.js'
+import YXmlElement from './YXmlElement.js'
+
+export { default as YXmlFragment } from './YXmlFragment.js'
+export { default as YXmlElement } from './YXmlElement.js'
+export { default as YXmlText } from './YXmlText.js'
+
+YXmlFragment._YXmlElement = YXmlElement

src/Util/EventHandler.js

@@ -0,0 +1,35 @@
+
+export default class EventHandler {
+  constructor () {
+    this.eventListeners = []
+  }
+  destroy () {
+    this.eventListeners = null
+  }
+  addEventListener (f) {
+    this.eventListeners.push(f)
+  }
+  removeEventListener (f) {
+    this.eventListeners = this.eventListeners.filter(function (g) {
+      return f !== g
+    })
+  }
+  removeAllEventListeners () {
+    this.eventListeners = []
+  }
+  callEventListeners (transaction, event) {
+    for (var i = 0; i < this.eventListeners.length; i++) {
+      try {
+        const f = this.eventListeners[i]
+        f(event)
+      } catch (e) {
+        /*
+          Your observer threw an error. This error was caught so that Yjs
+          can ensure data consistency! In order to debug this error you
+          have to check "Pause On Caught Exceptions" in developer tools.
+        */
+        console.error(e)
+      }
+    }
+  }
+}

src/Util/ID.js

@@ -0,0 +1,16 @@
+
+export default class ID {
+  constructor (user, clock) {
+    this.user = user
+    this.clock = clock
+  }
+  clone () {
+    return new ID(this.user, this.clock)
+  }
+  equals (id) {
+    return id !== null && id.user === this.user && id.clock === this.clock
+  }
+  lessThan (id) {
+    return this.user < id.user || (this.user === id.user && this.clock < id.clock)
+  }
+}

src/Util/NamedEventHandler.js

@@ -0,0 +1,46 @@
+export default class NamedEventHandler {
+  constructor () {
+    this._eventListener = new Map()
+  }
+  _getListener (name) {
+    let listeners = this._eventListener.get(name)
+    if (listeners === undefined) {
+      listeners = {
+        once: new Set(),
+        on: new Set()
+      }
+      this._eventListener.set(name, listeners)
+    }
+    return listeners
+  }
+  once (name, f) {
+    let listeners = this._getListener(name)
+    listeners.once.add(f)
+  }
+  on (name, f) {
+    let listeners = this._getListener(name)
+    listeners.on.add(f)
+  }
+  off (name, f) {
+    if (name == null || f == null) {
+      throw new Error('You must specify event name and function!')
+    }
+    const listener = this._eventListener.get(name)
+    if (listener !== undefined) {
+      listener.remove(f)
+    }
+  }
+  emit (name, ...args) {
+    const listener = this._eventListener.get(name)
+    if (listener !== undefined) {
+      listener.on.forEach(f => f.apply(null, args))
+      listener.once.forEach(f => f.apply(null, args))
+      listener.once = new Set()
+    } else if (name === 'error') {
+      console.error(args[0])
+    }
+  }
+  destroy () {
+    this._eventListener = null
+  }
+}

src/Util/RootID.js

@@ -0,0 +1,17 @@
+import { getReference } from './structReferences.js'
+
+export const RootFakeUserID = 0xFFFFFF
+
+export default class RootID {
+  constructor (name, typeConstructor) {
+    this.user = RootFakeUserID
+    this.name = name
+    this.type = getReference(typeConstructor)
+  }
+  equals (id) {
+    return id !== null && id.user === this.user && id.name === this.name && id.type === this.type
+  }
+  lessThan (id) {
+    return this.user < id.user || (this.user === id.user && (this.name < id.name || (this.name === id.name && this.type < id.type)))
+  }
+}

src/Util/Tree.js

@@ -0,0 +1,471 @@
+
+class N {
+  // A created node is always red!
+  constructor (val) {
+    this.val = val
+    this.color = true
+    this._left = null
+    this._right = null
+    this._parent = null
+  }
+  isRed () { return this.color }
+  isBlack () { return !this.color }
+  redden () { this.color = true; return this }
+  blacken () { this.color = false; return this }
+  get grandparent () {
+    return this.parent.parent
+  }
+  get parent () {
+    return this._parent
+  }
+  get sibling () {
+    return (this === this.parent.left)
+      ? this.parent.right : this.parent.left
+  }
+  get left () {
+    return this._left
+  }
+  get right () {
+    return this._right
+  }
+  set left (n) {
+    if (n !== null) {
+      n._parent = this
+    }
+    this._left = n
+  }
+  set right (n) {
+    if (n !== null) {
+      n._parent = this
+    }
+    this._right = n
+  }
+  rotateLeft (tree) {
+    var parent = this.parent
+    var newParent = this.right
+    var newRight = this.right.left
+    newParent.left = this
+    this.right = newRight
+    if (parent === null) {
+      tree.root = newParent
+      newParent._parent = null
+    } else if (parent.left === this) {
+      parent.left = newParent
+    } else if (parent.right === this) {
+      parent.right = newParent
+    } else {
+      throw new Error('The elements are wrongly connected!')
+    }
+  }
+  next () {
+    if (this.right !== null) {
+      // search the most left node in the right tree
+      var o = this.right
+      while (o.left !== null) {
+        o = o.left
+      }
+      return o
+    } else {
+      var p = this
+      while (p.parent !== null && p !== p.parent.left) {
+        p = p.parent
+      }
+      return p.parent
+    }
+  }
+  prev () {
+    if (this.left !== null) {
+      // search the most right node in the left tree
+      var o = this.left
+      while (o.right !== null) {
+        o = o.right
+      }
+      return o
+    } else {
+      var p = this
+      while (p.parent !== null && p !== p.parent.right) {
+        p = p.parent
+      }
+      return p.parent
+    }
+  }
+  rotateRight (tree) {
+    var parent = this.parent
+    var newParent = this.left
+    var newLeft = this.left.right
+    newParent.right = this
+    this.left = newLeft
+    if (parent === null) {
+      tree.root = newParent
+      newParent._parent = null
+    } else if (parent.left === this) {
+      parent.left = newParent
+    } else if (parent.right === this) {
+      parent.right = newParent
+    } else {
+      throw new Error('The elements are wrongly connected!')
+    }
+  }
+  getUncle () {
+    // we can assume that grandparent exists when this is called!
+    if (this.parent === this.parent.parent.left) {
+      return this.parent.parent.right
+    } else {
+      return this.parent.parent.left
+    }
+  }
+}
+
+/*
+ * This is a Red Black Tree implementation
+ */
+export default class Tree {
+  constructor () {
+    this.root = null
+    this.length = 0
+  }
+  findNext (id) {
+    var nextID = id.clone()
+    nextID.clock += 1
+    return this.findWithLowerBound(nextID)
+  }
+  findPrev (id) {
+    let prevID = id.clone()
+    prevID.clock -= 1
+    return this.findWithUpperBound(prevID)
+  }
+  findNodeWithLowerBound (from) {
+    var o = this.root
+    if (o === null) {
+      return null
+    } else {
+      while (true) {
+        if (from === null || (from.lessThan(o.val._id) && o.left !== null)) {
+          // o is included in the bound
+          // try to find an element that is closer to the bound
+          o = o.left
+        } else if (from !== null && o.val._id.lessThan(from)) {
+          // o is not within the bound, maybe one of the right elements is..
+          if (o.right !== null) {
+            o = o.right
+          } else {
+            // there is no right element. Search for the next bigger element,
+            // this should be within the bounds
+            return o.next()
+          }
+        } else {
+          return o
+        }
+      }
+    }
+  }
+  findNodeWithUpperBound (to) {
+    if (to === void 0) {
+      throw new Error('You must define from!')
+    }
+    var o = this.root
+    if (o === null) {
+      return null
+    } else {
+      while (true) {
+        if ((to === null || o.val._id.lessThan(to)) && o.right !== null) {
+          // o is included in the bound
+          // try to find an element that is closer to the bound
+          o = o.right
+        } else if (to !== null && to.lessThan(o.val._id)) {
+          // o is not within the bound, maybe one of the left elements is..
+          if (o.left !== null) {
+            o = o.left
+          } else {
+            // there is no left element. Search for the prev smaller element,
+            // this should be within the bounds
+            return o.prev()
+          }
+        } else {
+          return o
+        }
+      }
+    }
+  }
+  findSmallestNode () {
+    var o = this.root
+    while (o != null && o.left != null) {
+      o = o.left
+    }
+    return o
+  }
+  findWithLowerBound (from) {
+    var n = this.findNodeWithLowerBound(from)
+    return n == null ? null : n.val
+  }
+  findWithUpperBound (to) {
+    var n = this.findNodeWithUpperBound(to)
+    return n == null ? null : n.val
+  }
+  iterate (from, to, f) {
+    var o
+    if (from === null) {
+      o = this.findSmallestNode()
+    } else {
+      o = this.findNodeWithLowerBound(from)
+    }
+    while (
+      o !== null &&
+      (
+        to === null || // eslint-disable-line no-unmodified-loop-condition
+        o.val._id.lessThan(to) ||
+        o.val._id.equals(to)
+      )
+    ) {
+      f(o.val)
+      o = o.next()
+    }
+  }
+  find (id) {
+    let n = this.findNode(id)
+    if (n !== null) {
+      return n.val
+    } else {
+      return null
+    }
+  }
+  findNode (id) {
+    var o = this.root
+    if (o === null) {
+      return null
+    } else {
+      while (true) {
+        if (o === null) {
+          return null
+        }
+        if (id.lessThan(o.val._id)) {
+          o = o.left
+        } else if (o.val._id.lessThan(id)) {
+          o = o.right
+        } else {
+          return o
+        }
+      }
+    }
+  }
+  delete (id) {
+    var d = this.findNode(id)
+    if (d == null) {
+      // throw new Error('Element does not exist!')
+      return
+    }
+    this.length--
+    if (d.left !== null && d.right !== null) {
+      // switch d with the greates element in the left subtree.
+      // o should have at most one child.
+      var o = d.left
+      // find
+      while (o.right !== null) {
+        o = o.right
+      }
+      // switch
+      d.val = o.val
+      d = o
+    }
+    // d has at most one child
+    // let n be the node that replaces d
+    var isFakeChild
+    var child = d.left || d.right
+    if (child === null) {
+      isFakeChild = true
+      child = new N(null)
+      child.blacken()
+      d.right = child
+    } else {
+      isFakeChild = false
+    }
+
+    if (d.parent === null) {
+      if (!isFakeChild) {
+        this.root = child
+        child.blacken()
+        child._parent = null
+      } else {
+        this.root = null
+      }
+      return
+    } else if (d.parent.left === d) {
+      d.parent.left = child
+    } else if (d.parent.right === d) {
+      d.parent.right = child
+    } else {
+      throw new Error('Impossible!')
+    }
+    if (d.isBlack()) {
+      if (child.isRed()) {
+        child.blacken()
+      } else {
+        this._fixDelete(child)
+      }
+    }
+    this.root.blacken()
+    if (isFakeChild) {
+      if (child.parent.left === child) {
+        child.parent.left = null
+      } else if (child.parent.right === child) {
+        child.parent.right = null
+      } else {
+        throw new Error('Impossible #3')
+      }
+    }
+  }
+  _fixDelete (n) {
+    function isBlack (node) {
+      return node !== null ? node.isBlack() : true
+    }
+    function isRed (node) {
+      return node !== null ? node.isRed() : false
+    }
+    if (n.parent === null) {
+      // this can only be called after the first iteration of fixDelete.
+      return
+    }
+    // d was already replaced by the child
+    // d is not the root
+    // d and child are black
+    var sibling = n.sibling
+    if (isRed(sibling)) {
+      // make sibling the grandfather
+      n.parent.redden()
+      sibling.blacken()
+      if (n === n.parent.left) {
+        n.parent.rotateLeft(this)
+      } else if (n === n.parent.right) {
+        n.parent.rotateRight(this)
+      } else {
+        throw new Error('Impossible #2')
+      }
+      sibling = n.sibling
+    }
+    // parent, sibling, and children of n are black
+    if (n.parent.isBlack() &&
+      sibling.isBlack() &&
+      isBlack(sibling.left) &&
+      isBlack(sibling.right)
+    ) {
+      sibling.redden()
+      this._fixDelete(n.parent)
+    } else if (n.parent.isRed() &&
+      sibling.isBlack() &&
+      isBlack(sibling.left) &&
+      isBlack(sibling.right)
+    ) {
+      sibling.redden()
+      n.parent.blacken()
+    } else {
+      if (n === n.parent.left &&
+        sibling.isBlack() &&
+        isRed(sibling.left) &&
+        isBlack(sibling.right)
+      ) {
+        sibling.redden()
+        sibling.left.blacken()
+        sibling.rotateRight(this)
+        sibling = n.sibling
+      } else if (n === n.parent.right &&
+        sibling.isBlack() &&
+        isRed(sibling.right) &&
+        isBlack(sibling.left)
+      ) {
+        sibling.redden()
+        sibling.right.blacken()
+        sibling.rotateLeft(this)
+        sibling = n.sibling
+      }
+      sibling.color = n.parent.color
+      n.parent.blacken()
+      if (n === n.parent.left) {
+        sibling.right.blacken()
+        n.parent.rotateLeft(this)
+      } else {
+        sibling.left.blacken()
+        n.parent.rotateRight(this)
+      }
+    }
+  }
+  put (v) {
+    var node = new N(v)
+    if (this.root !== null) {
+      var p = this.root // p abbrev. parent
+      while (true) {
+        if (node.val._id.lessThan(p.val._id)) {
+          if (p.left === null) {
+            p.left = node
+            break
+          } else {
+            p = p.left
+          }
+        } else if (p.val._id.lessThan(node.val._id)) {
+          if (p.right === null) {
+            p.right = node
+            break
+          } else {
+            p = p.right
+          }
+        } else {
+          p.val = node.val
+          return p
+        }
+      }
+      this._fixInsert(node)
+    } else {
+      this.root = node
+    }
+    this.length++
+    this.root.blacken()
+    return node
+  }
+  _fixInsert (n) {
+    if (n.parent === null) {
+      n.blacken()
+      return
+    } else if (n.parent.isBlack()) {
+      return
+    }
+    var uncle = n.getUncle()
+    if (uncle !== null && uncle.isRed()) {
+      // Note: parent: red, uncle: red
+      n.parent.blacken()
+      uncle.blacken()
+      n.grandparent.redden()
+      this._fixInsert(n.grandparent)
+    } else {
+      // Note: parent: red, uncle: black or null
+      // Now we transform the tree in such a way that
+      // either of these holds:
+      //   1) grandparent.left.isRed
+      //     and grandparent.left.left.isRed
+      //   2) grandparent.right.isRed
+      //     and grandparent.right.right.isRed
+      if (n === n.parent.right && n.parent === n.grandparent.left) {
+        n.parent.rotateLeft(this)
+        // Since we rotated and want to use the previous
+        // cases, we need to set n in such a way that
+        // n.parent.isRed again
+        n = n.left
+      } else if (n === n.parent.left && n.parent === n.grandparent.right) {
+        n.parent.rotateRight(this)
+        // see above
+        n = n.right
+      }
+      // Case 1) or 2) hold from here on.
+      // Now traverse grandparent, make parent a black node
+      // on the highest level which holds two red nodes.
+      n.parent.blacken()
+      n.grandparent.redden()
+      if (n === n.parent.left) {
+        // Case 1
+        n.grandparent.rotateRight(this)
+      } else {
+        // Case 2
+        n.grandparent.rotateLeft(this)
+      }
+    }
+  }
+  flush () {}
+}

src/Util/UndoManager.js

@@ -0,0 +1,106 @@
+import ID from './ID.js'
+
+class ReverseOperation {
+  constructor (y, transaction) {
+    this.created = new Date()
+    const beforeState = transaction.beforeState
+    this.toState = new ID(y.userID, y.ss.getState(y.userID) - 1)
+    if (beforeState.has(y.userID)) {
+      this.fromState = new ID(y.userID, beforeState.get(y.userID))
+    } else {
+      this.fromState = this.toState
+    }
+    this.deletedStructs = transaction.deletedStructs
+  }
+}
+
+function isStructInScope (y, struct, scope) {
+  while (struct !== y) {
+    if (struct === scope) {
+      return true
+    }
+    struct = struct._parent
+  }
+  return false
+}
+
+function applyReverseOperation (y, scope, reverseBuffer) {
+  let performedUndo = false
+  y.transact(() => {
+    while (!performedUndo && reverseBuffer.length > 0) {
+      let undoOp = reverseBuffer.pop()
+      // make sure that it is possible to iterate {from}-{to}
+      y.os.getItemCleanStart(undoOp.fromState)
+      y.os.getItemCleanEnd(undoOp.toState)
+      y.os.iterate(undoOp.fromState, undoOp.toState, op => {
+        if (!op._deleted && isStructInScope(y, op, scope)) {
+          performedUndo = true
+          op._delete(y)
+        }
+      })
+      for (let op of undoOp.deletedStructs) {
+        if (
+          isStructInScope(y, op, scope) &&
+          op._parent !== y &&
+          !op._parent._deleted &&
+          (
+            op._parent._id.user !== y.userID ||
+            op._parent._id.clock < undoOp.fromState.clock ||
+            op._parent._id.clock > undoOp.fromState.clock
+          )
+        ) {
+          performedUndo = true
+          op = op._copy(undoOp.deletedStructs)
+          op._integrate(y)
+        }
+      }
+    }
+  })
+  return performedUndo
+}
+
+export default class UndoManager {
+  constructor (scope, options = {}) {
+    this.options = options
+    options.captureTimeout = options.captureTimeout == null ? 500 : options.captureTimeout
+    this._undoBuffer = []
+    this._redoBuffer = []
+    this._scope = scope
+    this._undoing = false
+    this._redoing = false
+    const y = scope._y
+    this.y = y
+    y.on('afterTransaction', (y, transaction, remote) => {
+      if (!remote && transaction.changedParentTypes.has(scope)) {
+        let reverseOperation = new ReverseOperation(y, transaction)
+        if (!this._undoing) {
+          let lastUndoOp = this._undoBuffer.length > 0 ? this._undoBuffer[this._undoBuffer.length - 1] : null
+          if (lastUndoOp !== null && reverseOperation.created - lastUndoOp.created <= options.captureTimeout) {
+            lastUndoOp.created = reverseOperation.created
+            lastUndoOp.toState = reverseOperation.toState
+            reverseOperation.deletedStructs.forEach(lastUndoOp.deletedStructs.add, lastUndoOp.deletedStructs)
+          } else {
+            this._undoBuffer.push(reverseOperation)
+          }
+          if (!this._redoing) {
+            this._redoBuffer = []
+          }
+        } else {
+          this._redoBuffer.push(reverseOperation)
+        }
+      }
+    })
+  }
+  undo () {
+    this._undoing = true
+    const performedUndo = applyReverseOperation(this.y, this._scope, this._undoBuffer)
+    this._undoing = false
+    return performedUndo
+  }
+  redo () {
+    this._redoing = true
+    const performedRedo = applyReverseOperation(this.y, this._scope, this._redoBuffer)
+    this._redoing = false
+    return performedRedo
+  }
+}

src/Util/YEvent.js

@@ -0,0 +1,28 @@
+
+export default class YEvent {
+  constructor (target) {
+    this.target = target
+    this.currentTarget = target
+  }
+  get path () {
+    const path = []
+    let type = this.target
+    const y = type._y
+    while (type !== this.currentTarget && type !== y) {
+      let parent = type._parent
+      if (type._parentSub !== null) {
+        path.unshift(type._parentSub)
+      } else {
+        // parent is array-ish
+        for (let [i, child] of parent) {
+          if (child === type) {
+            path.unshift(i)
+            break
+          }
+        }
+      }
+      type = parent
+    }
+    return path
+  }
+}

src/Util/defragmentItemContent.js

@@ -0,0 +1,57 @@
+
+import ID from '../Util/ID.js'
+import ItemJSON from '../Struct/ItemJSON.js'
+import ItemString from '../Struct/ItemString.js'
+
+/**
+ * Try to merge all items in os with their successors.
+ *
+ * Some transformations (like delete) fragment items.
+ * Item(c: 'ab') + Delete(1,1) + Delete(0, 1) -> Item(c: 'a',deleted);Item(c: 'b',deleted)
+ *
+ * This functions merges the fragmented nodes together:
+ * Item(c: 'a',deleted);Item(c: 'b',deleted) -> Item(c: 'ab', deleted)
+ *
+ * TODO: The Tree implementation does not support deletions in-spot.
+ *       This is why all deletions must be performed after the traversal.
+ *
+ */
+export function defragmentItemContent (y) {
+  const os = y.os
+  if (os.length < 2) {
+    return
+  }
+  let deletes = []
+  let node = os.findSmallestNode()
+  let next = node.next()
+  while (next !== null) {
+    let a = node.val
+    let b = next.val
+    if (
+      (a instanceof ItemJSON || a instanceof ItemString) &&
+      a.constructor === b.constructor &&
+      a._deleted === b._deleted &&
+      a._right === b &&
+      (new ID(a._id.user, a._id.clock + a._length)).equals(b._id)
+    ) {
+      a._right = b._right
+      if (a instanceof ItemJSON) {
+        a._content = a._content.concat(b._content)
+      } else if (a instanceof ItemString) {
+        a._content += b._content
+      }
+      // delete b later
+      deletes.push(b._id)
+      // do not iterate node!
+      // !(node = next)
+    } else {
+      // not able to merge node, get next node
+      node = next
+    }
+    // update next
+    next = next.next()
+  }
+  for (let i = deletes.length - 1; i >= 0; i--) {
+    os.delete(deletes[i])
+  }
+}

src/Util/generateUserID.js

@@ -0,0 +1,16 @@
+/* global crypto */
+
+export function generateUserID () {
+  if (typeof crypto !== 'undefined' && crypto.getRandomValue != null) {
+    // browser
+    let arr = new Uint32Array(1)
+    crypto.getRandomValues(arr)
+    return arr[0]
+  } else if (typeof crypto !== 'undefined' && crypto.randomBytes != null) {
+    // node
+    let buf = crypto.randomBytes(4)
+    return new Uint32Array(buf.buffer)[0]
+  } else {
+    return Math.ceil(Math.random() * 0xFFFFFFFF)
+  }
+}

src/Util/relativePosition.js

@@ -0,0 +1,59 @@
+import ID from './ID.js'
+import RootID from './RootID.js'
+
+export function getRelativePosition (type, offset) {
+  if (offset === 0) {
+    return ['startof', type._id.user, type._id.clock || null, type._id.name || null, type._id.type || null]
+  } else {
+    let t = type._start
+    while (t !== null) {
+      if (t._length >= offset) {
+        return [t._id.user, t._id.clock + offset - 1]
+      }
+      if (t._right === null) {
+        return [t._id.user, t._id.clock + t._length - 1]
+      }
+      if (!t._deleted) {
+        offset -= t._length
+      }
+      t = t._right
+    }
+    return null
+  }
+}
+
+export function fromRelativePosition (y, rpos) {
+  if (rpos[0] === 'startof') {
+    let id
+    if (rpos[3] === null) {
+      id = new ID(rpos[1], rpos[2])
+    } else {
+      id = new RootID(rpos[3], rpos[4])
+    }
+    return {
+      type: y.os.get(id),
+      offset: 0
+    }
+  } else {
+    let offset = 0
+    let struct = y.os.findNodeWithUpperBound(new ID(rpos[0], rpos[1])).val
+    const parent = struct._parent
+    if (parent._deleted) {
+      return null
+    }
+    if (!struct._deleted) {
+      offset = rpos[1] - struct._id.clock + 1
+    }
+    struct = struct._left
+    while (struct !== null) {
+      if (!struct._deleted) {
+        offset += struct._length
+      }
+      struct = struct._left
+    }
+    return {
+      type: parent,
+      offset: offset
+    }
+  }
+}

src/Util/structReferences.js

@@ -0,0 +1,37 @@
+import YArray from '../Type/YArray.js'
+import YMap from '../Type/YMap.js'
+import YText from '../Type/YText.js'
+import YXmlFragment from '../Type/y-xml/YXmlFragment.js'
+import YXmlElement from '../Type/y-xml/YXmlElement.js'
+import YXmlText from '../Type/y-xml/YXmlText.js'
+
+import Delete from '../Struct/Delete.js'
+import ItemJSON from '../Struct/ItemJSON.js'
+import ItemString from '../Struct/ItemString.js'
+
+const structs = new Map()
+const references = new Map()
+
+function addStruct (reference, structConstructor) {
+  structs.set(reference, structConstructor)
+  references.set(structConstructor, reference)
+}
+
+export function getStruct (reference) {
+  return structs.get(reference)
+}
+
+export function getReference (typeConstructor) {
+  return references.get(typeConstructor)
+}
+
+addStruct(0, ItemJSON)
+addStruct(1, ItemString)
+addStruct(2, Delete)
+
+addStruct(3, YArray)
+addStruct(4, YMap)
+addStruct(5, YText)
+addStruct(6, YXmlFragment)
+addStruct(7, YXmlElement)
+addStruct(8, YXmlText)

src/Util/writeJSONToType.js

@@ -0,0 +1,33 @@
+
+import YMap from '../Type/YMap'
+import YArray from '../Type/YArray'
+
+export function writeObjectToYMap (object, type) {
+  for (var key in object) {
+    var val = object[key]
+    if (Array.isArray(val)) {
+      type.set(key, YArray)
+      writeArrayToYArray(val, type.get(key))
+    } else if (typeof val === 'object') {
+      type.set(key, YMap)
+      writeObjectToYMap(val, type.get(key))
+    } else {
+      type.set(key, val)
+    }
+  }
+}
+
+export function writeArrayToYArray (array, type) {
+  for (var i = array.length - 1; i >= 0; i--) {
+    var val = array[i]
+    if (Array.isArray(val)) {
+      type.insert(0, [YArray])
+      writeArrayToYArray(val, type.get(0))
+    } else if (typeof val === 'object') {
+      type.insert(0, [YMap])
+      writeObjectToYMap(val, type.get(0))
+    } else {
+      type.insert(0, [val])
+    }
+  }
+}

src/Utils.js

@@ -1,736 +0,0 @@
-/* @flow */
-'use strict'
-
-/*
-  EventHandler is an helper class for constructing custom types.
-
-  Why: When constructing custom types, you sometimes want your types to work
-  synchronous: E.g.
-  ``` Synchronous
-    mytype.setSomething("yay")
-    mytype.getSomething() === "yay"
-  ```
-  versus
-  ``` Asynchronous
-    mytype.setSomething("yay")
-    mytype.getSomething() === undefined
-    mytype.waitForSomething().then(function(){
-      mytype.getSomething() === "yay"
-    })
-  ```
-
-  The structures usually work asynchronously (you have to wait for the
-  database request to finish). EventHandler helps you to make your type
-  synchronous.
-*/
-module.exports = function (Y /* : any*/) {
-  Y.utils = {}
-
-  class EventListenerHandler {
-    constructor () {
-      this.eventListeners = []
-    }
-    destroy () {
-      this.eventListeners = null
-    }
-     /*
-      Basic event listener boilerplate...
-    */
-    addEventListener (f) {
-      this.eventListeners.push(f)
-    }
-    removeEventListener (f) {
-      this.eventListeners = this.eventListeners.filter(function (g) {
-        return f !== g
-      })
-    }
-    removeAllEventListeners () {
-      this.eventListeners = []
-    }
-    callEventListeners (event) {
-      for (var i = 0; i < this.eventListeners.length; i++) {
-        try {
-          this.eventListeners[i](event)
-        } catch (e) {
-          console.error('User events must not throw Errors!')
-        }
-      }
-    }
-  }
-  Y.utils.EventListenerHandler = EventListenerHandler
-
-  class EventHandler extends EventListenerHandler {
-    /* ::
-    waiting: Array<Insertion | Deletion>;
-    awaiting: number;
-    onevent: Function;
-    eventListeners: Array<Function>;
-    */
-    /*
-      onevent: is called when the structure changes.
-
-      Note: "awaiting opertations" is used to denote operations that were
-      prematurely called. Events for received operations can not be executed until
-      all prematurely called operations were executed ("waiting operations")
-    */
-    constructor (onevent /* : Function */) {
-      super()
-      this.waiting = []
-      this.awaiting = 0
-      this.onevent = onevent
-    }
-    destroy () {
-      super.destroy()
-      this.waiting = null
-      this.awaiting = null
-      this.onevent = null
-    }
-    /*
-      Call this when a new operation arrives. It will be executed right away if
-      there are no waiting operations, that you prematurely executed
-    */
-    receivedOp (op) {
-      if (this.awaiting <= 0) {
-        this.onevent(op)
-      } else if (op.struct === 'Delete') {
-        var self = this
-        var checkDelete = function checkDelete (d) {
-          if (d.length == null) {
-            throw new Error('This shouldn\'t happen! d.length must be defined!')
-          }
-          // we check if o deletes something in self.waiting
-          // if so, we remove the deleted operation
-          for (var w = 0; w < self.waiting.length; w++) {
-            var i = self.waiting[w]
-            if (i.struct === 'Insert' && i.id[0] === d.target[0]) {
-              var iLength = i.hasOwnProperty('content') ? i.content.length : 1
-              var dStart = d.target[1]
-              var dEnd = d.target[1] + (d.length || 1)
-              var iStart = i.id[1]
-              var iEnd = i.id[1] + iLength
-              // Check if they don't overlap
-              if (iEnd <= dStart || dEnd <= iStart) {
-                // no overlapping
-                continue
-              }
-              // we check all overlapping cases. All cases:
-              /*
-                1)  iiiii
-                      ddddd
-                    --> modify i and d
-                2)  iiiiiii
-                      ddddd
-                    --> modify i, remove d
-                3)  iiiiiii
-                      ddd
-                    --> remove d, modify i, and create another i (for the right hand side)
-                4)  iiiii
-                    ddddddd
-                    --> remove i, modify d
-                5)  iiiiiii
-                    ddddddd
-                    --> remove both i and d (**)
-                6)  iiiiiii
-                    ddddd
-                    --> modify i, remove d
-                7)    iii
-                    ddddddd
-                    --> remove i, create and apply two d with checkDelete(d) (**)
-                8)    iiiii
-                    ddddddd
-                    --> remove i, modify d (**)
-                9)    iiiii
-                    ddddd
-                    --> modify i and d
-                (**) (also check if i contains content or type)
-              */
-              // TODO: I left some debugger statements, because I want to debug all cases once in production. REMEMBER END TODO
-              if (iStart < dStart) {
-                if (dStart < iEnd) {
-                  if (iEnd < dEnd) {
-                    // Case 1
-                    // remove the right part of i's content
-                    i.content.splice(dStart - iStart)
-                    // remove the start of d's deletion
-                    d.length = dEnd - iEnd
-                    d.target = [d.target[0], iEnd]
-                    continue
-                  } else if (iEnd === dEnd) {
-                    // Case 2
-                    i.content.splice(dStart - iStart)
-                    // remove d, we do that by simply ending this function
-                    return
-                  } else { // (dEnd < iEnd)
-                    // Case 3
-                    var newI = {
-                      id: [i.id[0], dEnd],
-                      content: i.content.slice(dEnd - iStart),
-                      struct: 'Insert'
-                    }
-                    self.waiting.push(newI)
-                    i.content.splice(dStart - iStart)
-                    return
-                  }
-                }
-              } else if (dStart === iStart) {
-                if (iEnd < dEnd) {
-                  // Case 4
-                  d.length = dEnd - iEnd
-                  d.target = [d.target[0], iEnd]
-                  i.content = []
-                  continue
-                } else if (iEnd === dEnd) {
-                  // Case 5
-                  self.waiting.splice(w, 1)
-                  return
-                } else { // (dEnd < iEnd)
-                  // Case 6
-                  i.content = i.content.slice(dEnd - iStart)
-                  i.id = [i.id[0], dEnd]
-                  return
-                }
-              } else { // (dStart < iStart)
-                if (iStart < dEnd) {
-                  // they overlap
-                  /*
-                  7)    iii
-                      ddddddd
-                      --> remove i, create and apply two d with checkDelete(d) (**)
-                  8)    iiiii
-                      ddddddd
-                      --> remove i, modify d (**)
-                  9)    iiiii
-                      ddddd
-                      --> modify i and d
-                  */
-                  if (iEnd < dEnd) {
-                    // Case 7
-                    // debugger // TODO: You did not test this case yet!!!! (add the debugger here)
-                    self.waiting.splice(w, 1)
-                    checkDelete({
-                      target: [d.target[0], dStart],
-                      length: iStart - dStart,
-                      struct: 'Delete'
-                    })
-                    checkDelete({
-                      target: [d.target[0], iEnd],
-                      length: iEnd - dEnd,
-                      struct: 'Delete'
-                    })
-                    return
-                  } else if (iEnd === dEnd) {
-                    // Case 8
-                    self.waiting.splice(w, 1)
-                    w--
-                    d.length -= iLength
-                    continue
-                  } else { // dEnd < iEnd
-                    // Case 9
-                    d.length = iStart - dStart
-                    i.content.splice(0, dEnd - iStart)
-                    i.id = [i.id[0], dEnd]
-                    continue
-                  }
-                }
-              }
-            }
-          }
-          // finished with remaining operations
-          self.waiting.push(d)
-        }
-        checkDelete(op)
-      } else {
-        this.waiting.push(op)
-      }
-    }
-    /*
-      You created some operations, and you want the `onevent` function to be
-      called right away. Received operations will not be executed untill all
-      prematurely called operations are executed
-    */
-    awaitAndPrematurelyCall (ops) {
-      this.awaiting++
-      ops.map(Y.utils.copyOperation).forEach(this.onevent)
-    }
-    * awaitOps (transaction, f, args) {
-      function notSoSmartSort (array) {
-        // this function sorts insertions in a executable order
-        var result = []
-        while (array.length > 0) {
-          for (var i = 0; i < array.length; i++) {
-            var independent = true
-            for (var j = 0; j < array.length; j++) {
-              if (Y.utils.matchesId(array[j], array[i].left)) {
-                // array[i] depends on array[j]
-                independent = false
-                break
-              }
-            }
-            if (independent) {
-              result.push(array.splice(i, 1)[0])
-              i--
-            }
-          }
-        }
-        return result
-      }
-      var before = this.waiting.length
-      // somehow create new operations
-      yield* f.apply(transaction, args)
-      // remove all appended ops / awaited ops
-      this.waiting.splice(before)
-      if (this.awaiting > 0) this.awaiting--
-      // if there are no awaited ops anymore, we can update all waiting ops, and send execute them (if there are still no awaited ops)
-      if (this.awaiting === 0 && this.waiting.length > 0) {
-        // update all waiting ops
-        for (let i = 0; i < this.waiting.length; i++) {
-          var o = this.waiting[i]
-          if (o.struct === 'Insert') {
-            var _o = yield* transaction.getInsertion(o.id)
-            if (!Y.utils.compareIds(_o.id, o.id)) {
-              // o got extended
-              o.left = [o.id[0], o.id[1] - 1]
-            } else if (_o.left == null) {
-              o.left = null
-            } else {
-              // find next undeleted op
-              var left = yield* transaction.getInsertion(_o.left)
-              while (left.deleted != null) {
-                if (left.left != null) {
-                  left = yield* transaction.getInsertion(left.left)
-                } else {
-                  left = null
-                  break
-                }
-              }
-              o.left = left != null ? Y.utils.getLastId(left) : null
-            }
-          }
-        }
-        // the previous stuff was async, so we have to check again!
-        // We also pull changes from the bindings, if there exists such a method, this could increase awaiting too
-        if (this._pullChanges != null) {
-          this._pullChanges()
-        }
-        if (this.awaiting === 0) {
-          // sort by type, execute inserts first
-          var ins = []
-          var dels = []
-          this.waiting.forEach(function (o) {
-            if (o.struct === 'Delete') {
-              dels.push(o)
-            } else {
-              ins.push(o)
-            }
-          })
-          this.waiting = []
-          // put in executable order
-          ins = notSoSmartSort(ins)
-          // this.onevent can trigger the creation of another operation
-          // -> check if this.awaiting increased & stop computation if it does
-          for (var i = 0; i < ins.length; i++) {
-            if (this.awaiting === 0) {
-              this.onevent(ins[i])
-            } else {
-              this.waiting = this.waiting.concat(ins.slice(i))
-              break
-            }
-          }
-          for (i = 0; i < dels.length; i++) {
-            if (this.awaiting === 0) {
-              this.onevent(dels[i])
-            } else {
-              this.waiting = this.waiting.concat(dels.slice(i))
-              break
-            }
-          }
-        }
-      }
-    }
-    // TODO: Remove awaitedInserts and awaitedDeletes in favor of awaitedOps, as they are deprecated and do not always work
-    // Do this in one of the coming releases that are breaking anyway
-    /*
-      Call this when you successfully awaited the execution of n Insert operations
-    */
-    awaitedInserts (n) {
-      var ops = this.waiting.splice(this.waiting.length - n)
-      for (var oid = 0; oid < ops.length; oid++) {
-        var op = ops[oid]
-        if (op.struct === 'Insert') {
-          for (var i = this.waiting.length - 1; i >= 0; i--) {
-            let w = this.waiting[i]
-            // TODO: do I handle split operations correctly here? Super unlikely, but yeah..
-            // Also: can this case happen? Can op be inserted in the middle of a larger op that is in $waiting?
-            if (w.struct === 'Insert') {
-              if (Y.utils.matchesId(w, op.left)) {
-                // include the effect of op in w
-                w.right = op.id
-                // exclude the effect of w in op
-                op.left = w.left
-              } else if (Y.utils.compareIds(w.id, op.right)) {
-                // similar..
-                w.left = Y.utils.getLastId(op)
-                op.right = w.right
-              }
-            }
-          }
-        } else {
-          throw new Error('Expected Insert Operation!')
-        }
-      }
-      this._tryCallEvents(n)
-    }
-    /*
-      Call this when you successfully awaited the execution of n Delete operations
-    */
-    awaitedDeletes (n, newLeft) {
-      var ops = this.waiting.splice(this.waiting.length - n)
-      for (var j = 0; j < ops.length; j++) {
-        var del = ops[j]
-        if (del.struct === 'Delete') {
-          if (newLeft != null) {
-            for (var i = 0; i < this.waiting.length; i++) {
-              let w = this.waiting[i]
-              // We will just care about w.left
-              if (w.struct === 'Insert' && Y.utils.compareIds(del.target, w.left)) {
-                w.left = newLeft
-              }
-            }
-          }
-        } else {
-          throw new Error('Expected Delete Operation!')
-        }
-      }
-      this._tryCallEvents(n)
-    }
-    /* (private)
-      Try to execute the events for the waiting operations
-    */
-    _tryCallEvents () {
-      function notSoSmartSort (array) {
-        var result = []
-        while (array.length > 0) {
-          for (var i = 0; i < array.length; i++) {
-            var independent = true
-            for (var j = 0; j < array.length; j++) {
-              if (Y.utils.matchesId(array[j], array[i].left)) {
-                // array[i] depends on array[j]
-                independent = false
-                break
-              }
-            }
-            if (independent) {
-              result.push(array.splice(i, 1)[0])
-              i--
-            }
-          }
-        }
-        return result
-      }
-      if (this.awaiting > 0) this.awaiting--
-      if (this.awaiting === 0 && this.waiting.length > 0) {
-        var ins = []
-        var dels = []
-        this.waiting.forEach(function (o) {
-          if (o.struct === 'Delete') {
-            dels.push(o)
-          } else {
-            ins.push(o)
-          }
-        })
-        ins = notSoSmartSort(ins)
-        ins.forEach(this.onevent)
-        dels.forEach(this.onevent)
-        this.waiting = []
-      }
-    }
-  }
-  Y.utils.EventHandler = EventHandler
-
-  /*
-    A wrapper for the definition of a custom type.
-    Every custom type must have three properties:
-
-    * struct
-      - Structname of this type
-    * initType
-      - Given a model, creates a custom type
-    * class
-      - the constructor of the custom type (e.g. in order to inherit from a type)
-  */
-  class CustomType { // eslint-disable-line
-    /* ::
-    struct: any;
-    initType: any;
-    class: Function;
-    name: String;
-    */
-    constructor (def) {
-      if (def.struct == null ||
-        def.initType == null ||
-        def.class == null ||
-        def.name == null
-      ) {
-        throw new Error('Custom type was not initialized correctly!')
-      }
-      this.struct = def.struct
-      this.initType = def.initType
-      this.class = def.class
-      this.name = def.name
-      if (def.appendAdditionalInfo != null) {
-        this.appendAdditionalInfo = def.appendAdditionalInfo
-      }
-      this.parseArguments = (def.parseArguments || function () {
-        return [this]
-      }).bind(this)
-      this.parseArguments.typeDefinition = this
-    }
-  }
-  Y.utils.CustomType = CustomType
-
-  Y.utils.isTypeDefinition = function isTypeDefinition (v) {
-    if (v != null) {
-      if (v instanceof Y.utils.CustomType) return [v]
-      else if (v.constructor === Array && v[0] instanceof Y.utils.CustomType) return v
-      else if (v instanceof Function && v.typeDefinition instanceof Y.utils.CustomType) return [v.typeDefinition]
-    }
-    return false
-  }
-
-  /*
-    Make a flat copy of an object
-    (just copy properties)
-  */
-  function copyObject (o) {
-    var c = {}
-    for (var key in o) {
-      c[key] = o[key]
-    }
-    return c
-  }
-  Y.utils.copyObject = copyObject
-
-  /*
-    Copy an operation, so that it can be manipulated.
-    Note: You must not change subproperties (except o.content)!
-  */
-  function copyOperation (o) {
-    o = copyObject(o)
-    if (o.content != null) {
-      o.content = o.content.map(function (c) { return c })
-    }
-    return o
-  }
-
-  Y.utils.copyOperation = copyOperation
-
-  /*
-    Defines a smaller relation on Id's
-  */
-  function smaller (a, b) {
-    return a[0] < b[0] || (a[0] === b[0] && (a[1] < b[1] || typeof a[1] < typeof b[1]))
-  }
-  Y.utils.smaller = smaller
-
-  function inDeletionRange (del, ins) {
-    return del.target[0] === ins[0] && del.target[1] <= ins[1] && ins[1] < del.target[1] + (del.length || 1)
-  }
-  Y.utils.inDeletionRange = inDeletionRange
-
-  function compareIds (id1, id2) {
-    if (id1 == null || id2 == null) {
-      return id1 === id2
-    } else {
-      return id1[0] === id2[0] && id1[1] === id2[1]
-    }
-  }
-  Y.utils.compareIds = compareIds
-
-  function matchesId (op, id) {
-    if (id == null || op == null) {
-      return id === op
-    } else {
-      if (id[0] === op.id[0]) {
-        if (op.content == null) {
-          return id[1] === op.id[1]
-        } else {
-          return id[1] >= op.id[1] && id[1] < op.id[1] + op.content.length
-        }
-      }
-    }
-  }
-  Y.utils.matchesId = matchesId
-
-  function getLastId (op) {
-    if (op.content == null || op.content.length === 1) {
-      return op.id
-    } else {
-      return [op.id[0], op.id[1] + op.content.length - 1]
-    }
-  }
-  Y.utils.getLastId = getLastId
-
-  function createEmptyOpsArray (n) {
-    var a = new Array(n)
-    for (var i = 0; i < a.length; i++) {
-      a[i] = {
-        id: [null, null]
-      }
-    }
-    return a
-  }
-
-  function createSmallLookupBuffer (Store) {
-    /*
-      This buffer implements a very small buffer that temporarily stores operations
-      after they are read / before they are written.
-      The buffer basically implements FIFO. Often requested lookups will be re-queued every time they are looked up / written.
-
-      It can speed up lookups on Operation Stores and State Stores. But it does not require notable use of memory or processing power.
-
-      Good for os and ss, bot not for ds (because it often uses methods that require a flush)
-
-      I tried to optimize this for performance, therefore no highlevel operations.
-    */
-    class SmallLookupBuffer extends Store {
-      constructor (arg1, arg2) {
-        // super(...arguments) -- do this when this is supported by stable nodejs
-        super(arg1, arg2)
-        this.writeBuffer = createEmptyOpsArray(5)
-        this.readBuffer = createEmptyOpsArray(10)
-      }
-      * find (id, noSuperCall) {
-        var i, r
-        for (i = this.readBuffer.length - 1; i >= 0; i--) {
-          r = this.readBuffer[i]
-          // we don't have to use compareids, because id is always defined!
-          if (r.id[1] === id[1] && r.id[0] === id[0]) {
-            // found r
-            // move r to the end of readBuffer
-            for (; i < this.readBuffer.length - 1; i++) {
-              this.readBuffer[i] = this.readBuffer[i + 1]
-            }
-            this.readBuffer[this.readBuffer.length - 1] = r
-            return r
-          }
-        }
-        var o
-        for (i = this.writeBuffer.length - 1; i >= 0; i--) {
-          r = this.writeBuffer[i]
-          if (r.id[1] === id[1] && r.id[0] === id[0]) {
-            o = r
-            break
-          }
-        }
-        if (i < 0 && noSuperCall === undefined) {
-          // did not reach break in last loop
-          // read id and put it to the end of readBuffer
-          o = yield* super.find(id)
-        }
-        if (o != null) {
-          for (i = 0; i < this.readBuffer.length - 1; i++) {
-            this.readBuffer[i] = this.readBuffer[i + 1]
-          }
-          this.readBuffer[this.readBuffer.length - 1] = o
-        }
-        return o
-      }
-      * put (o) {
-        var id = o.id
-        var i, r // helper variables
-        for (i = this.writeBuffer.length - 1; i >= 0; i--) {
-          r = this.writeBuffer[i]
-          if (r.id[1] === id[1] && r.id[0] === id[0]) {
-            // is already in buffer
-            // forget r, and move o to the end of writeBuffer
-            for (; i < this.writeBuffer.length - 1; i++) {
-              this.writeBuffer[i] = this.writeBuffer[i + 1]
-            }
-            this.writeBuffer[this.writeBuffer.length - 1] = o
-            break
-          }
-        }
-        if (i < 0) {
-          // did not reach break in last loop
-          // write writeBuffer[0]
-          var write = this.writeBuffer[0]
-          if (write.id[0] !== null) {
-            yield* super.put(write)
-          }
-          // put o to the end of writeBuffer
-          for (i = 0; i < this.writeBuffer.length - 1; i++) {
-            this.writeBuffer[i] = this.writeBuffer[i + 1]
-          }
-          this.writeBuffer[this.writeBuffer.length - 1] = o
-        }
-        // check readBuffer for every occurence of o.id, overwrite if found
-        // whether found or not, we'll append o to the readbuffer
-        for (i = 0; i < this.readBuffer.length - 1; i++) {
-          r = this.readBuffer[i + 1]
-          if (r.id[1] === id[1] && r.id[0] === id[0]) {
-            this.readBuffer[i] = o
-          } else {
-            this.readBuffer[i] = r
-          }
-        }
-        this.readBuffer[this.readBuffer.length - 1] = o
-      }
-      * delete (id) {
-        var i, r
-        for (i = 0; i < this.readBuffer.length; i++) {
-          r = this.readBuffer[i]
-          if (r.id[1] === id[1] && r.id[0] === id[0]) {
-            this.readBuffer[i] = {
-              id: [null, null]
-            }
-          }
-        }
-        yield* this.flush()
-        yield* super.delete(id)
-      }
-      * findWithLowerBound (id) {
-        var o = yield* this.find(id, true)
-        if (o != null) {
-          return o
-        } else {
-          yield* this.flush()
-          return yield* super.findWithLowerBound.apply(this, arguments)
-        }
-      }
-      * findWithUpperBound (id) {
-        var o = yield* this.find(id, true)
-        if (o != null) {
-          return o
-        } else {
-          yield* this.flush()
-          return yield* super.findWithUpperBound.apply(this, arguments)
-        }
-      }
-      * findNext () {
-        yield* this.flush()
-        return yield* super.findNext.apply(this, arguments)
-      }
-      * findPrev () {
-        yield* this.flush()
-        return yield* super.findPrev.apply(this, arguments)
-      }
-      * iterate () {
-        yield* this.flush()
-        yield* super.iterate.apply(this, arguments)
-      }
-      * flush () {
-        for (var i = 0; i < this.writeBuffer.length; i++) {
-          var write = this.writeBuffer[i]
-          if (write.id[0] !== null) {
-            yield* super.put(write)
-            this.writeBuffer[i] = {
-              id: [null, null]
-            }
-          }
-        }
-      }
-    }
-    return SmallLookupBuffer
-  }
-  Y.utils.createSmallLookupBuffer = createSmallLookupBuffer
-}

src/Y.js

@@ -0,0 +1,180 @@
+import DeleteStore from './Store/DeleteStore.js'
+import OperationStore from './Store/OperationStore.js'
+import StateStore from './Store/StateStore.js'
+import { generateUserID } from './Util/generateUserID.js'
+import RootID from './Util/RootID.js'
+import NamedEventHandler from './Util/NamedEventHandler.js'
+import UndoManager from './Util/UndoManager.js'
+
+import { messageToString, messageToRoomname } from './MessageHandler/messageToString.js'
+
+import Connector from './Connector.js'
+import Persistence from './Persistence.js'
+import YArray from './Type/YArray.js'
+import YMap from './Type/YMap.js'
+import YText from './Type/YText.js'
+import { YXmlFragment, YXmlElement, YXmlText } from './Type/y-xml/y-xml.js'
+import BinaryDecoder from './Binary/Decoder.js'
+import { getRelativePosition, fromRelativePosition } from './Util/relativePosition.js'
+
+import debug from 'debug'
+import Transaction from './Transaction.js'
+
+export default class Y extends NamedEventHandler {
+  constructor (opts) {
+    super()
+    this._opts = opts
+    this.userID = opts._userID != null ? opts._userID : generateUserID()
+    this.share = {}
+    this.ds = new DeleteStore(this)
+    this.os = new OperationStore(this)
+    this.ss = new StateStore(this)
+    this.connector = new Y[opts.connector.name](this, opts.connector)
+    if (opts.persistence != null) {
+      this.persistence = new Y[opts.persistence.name](this, opts.persistence)
+      this.persistence.retrieveContent()
+    } else {
+      this.persistence = null
+    }
+    this.connected = true
+    this._missingStructs = new Map()
+    this._readyToIntegrate = []
+    this._transaction = null
+  }
+  _beforeChange () {}
+  transact (f, remote = false) {
+    let initialCall = this._transaction === null
+    if (initialCall) {
+      this._transaction = new Transaction(this)
+      this.emit('beforeTransaction', this, this._transaction, remote)
+    }
+    try {
+      f(this)
+    } catch (e) {
+      console.error(e)
+    }
+    if (initialCall) {
+      const transaction = this._transaction
+      this._transaction = null
+      // emit change events on changed types
+      transaction.changedTypes.forEach(function (subs, type) {
+        if (!type._deleted) {
+          type._callObserver(transaction, subs, remote)
+        }
+      })
+      transaction.changedParentTypes.forEach(function (events, type) {
+        if (!type._deleted) {
+          events = events
+            .filter(event =>
+              !event.target._deleted
+            )
+          events
+            .forEach(event => {
+              event.currentTarget = type
+            })
+          // we don't have to check for events.length
+          // because there is no way events is empty..
+          type._deepEventHandler.callEventListeners(transaction, events)
+        }
+      })
+      // when all changes & events are processed, emit afterTransaction event
+      this.emit('afterTransaction', this, transaction, remote)
+    }
+  }
+  // fake _start for root properties (y.set('name', type))
+  get _start () {
+    return null
+  }
+  set _start (start) {
+    return null
+  }
+  get room () {
+    return this._opts.connector.room
+  }
+  define (name, TypeConstructor) {
+    let id = new RootID(name, TypeConstructor)
+    let type = this.os.get(id)
+    if (type === null) {
+      type = new TypeConstructor()
+      type._id = id
+      type._parent = this
+      type._integrate(this)
+      if (this.share[name] !== undefined) {
+        throw new Error('Type is already defined with a different constructor!')
+      }
+    }
+    if (this.share[name] === undefined) {
+      this.share[name] = type
+    }
+    return type
+  }
+  get (name) {
+    return this.share[name]
+  }
+  disconnect () {
+    if (this.connected) {
+      this.connected = false
+      return this.connector.disconnect()
+    } else {
+      return Promise.resolve()
+    }
+  }
+  reconnect () {
+    if (!this.connected) {
+      this.connected = true
+      return this.connector.reconnect()
+    } else {
+      return Promise.resolve()
+    }
+  }
+  destroy () {
+    this.share = null
+    if (this.connector.destroy != null) {
+      this.connector.destroy()
+    } else {
+      this.connector.disconnect()
+    }
+    this.os = null
+    this.ds = null
+    this.ss = null
+  }
+  whenSynced () {
+    return new Promise(resolve => {
+      this.once('synced', () => {
+        resolve()
+      })
+    })
+  }
+}
+
+Y.extend = function extendYjs () {
+  for (var i = 0; i < arguments.length; i++) {
+    var f = arguments[i]
+    if (typeof f === 'function') {
+      f(Y)
+    } else {
+      throw new Error('Expected a function!')
+    }
+  }
+}
+
+// TODO: The following assignments should be moved to yjs-dist
+Y.AbstractConnector = Connector
+Y.Persisence = Persistence
+Y.Array = YArray
+Y.Map = YMap
+Y.Text = YText
+Y.XmlElement = YXmlElement
+Y.XmlFragment = YXmlFragment
+Y.XmlText = YXmlText
+
+Y.utils = {
+  BinaryDecoder,
+  UndoManager,
+  getRelativePosition,
+  fromRelativePosition
+}
+
+Y.debug = debug
+debug.formatters.Y = messageToString
+debug.formatters.y = messageToRoomname

src/y-dist.cjs.js

@@ -0,0 +1,3 @@
+
+import Y from './Y.js'
+export default Y

src/y.js

@@ -1,186 +0,0 @@
-/* @flow */
-'use strict'
-
-require('./Connector.js')(Y)
-require('./Database.js')(Y)
-require('./Transaction.js')(Y)
-require('./Struct.js')(Y)
-require('./Utils.js')(Y)
-require('./Connectors/Test.js')(Y)
-
-var requiringModules = {}
-
-module.exports = Y
-Y.requiringModules = requiringModules
-
-Y.extend = function (name, value) {
-  if (value instanceof Y.utils.CustomType) {
-    Y[name] = value.parseArguments
-  } else {
-    Y[name] = value
-  }
-  if (requiringModules[name] != null) {
-    requiringModules[name].resolve()
-    delete requiringModules[name]
-  }
-}
-
-Y.requestModules = requestModules
-function requestModules (modules) {
-  // determine if this module was compiled for es5 or es6 (y.js vs. y.es6)
-  // if Insert.execute is a Function, then it isnt a generator..
-  // then load the es5(.js) files..
-  var extention = typeof regeneratorRuntime !== 'undefined' ? '.js' : '.es6'
-  var promises = []
-  for (var i = 0; i < modules.length; i++) {
-    var module = modules[i].split('(')[0]
-    var modulename = 'y-' + module.toLowerCase()
-    if (Y[module] == null) {
-      if (requiringModules[module] == null) {
-        // module does not exist
-        if (typeof window !== 'undefined' && window.Y !== 'undefined') {
-          var imported = document.createElement('script')
-          imported.src = Y.sourceDir + '/' + modulename + '/' + modulename + extention
-          document.head.appendChild(imported)
-
-          let requireModule = {}
-          requiringModules[module] = requireModule
-          requireModule.promise = new Promise(function (resolve) {
-            requireModule.resolve = resolve
-          })
-          promises.push(requireModule.promise)
-        } else {
-          console.info('YJS: Please do not depend on automatic requiring of modules anymore! Extend modules as follows `require(\'y-modulename\')(Y)`')
-          require(modulename)(Y)
-        }
-      } else {
-        promises.push(requiringModules[modules[i]].promise)
-      }
-    }
-  }
-  return Promise.all(promises)
-}
-
-/* ::
-type MemoryOptions = {
-  name: 'memory'
-}
-type IndexedDBOptions = {
-  name: 'indexeddb',
-  namespace: string
-}
-type DbOptions = MemoryOptions | IndexedDBOptions
-
-type WebRTCOptions = {
-  name: 'webrtc',
-  room: string
-}
-type WebsocketsClientOptions = {
-  name: 'websockets-client',
-  room: string
-}
-type ConnectionOptions = WebRTCOptions | WebsocketsClientOptions
-
-type YOptions = {
-  connector: ConnectionOptions,
-  db: DbOptions,
-  types: Array<TypeName>,
-  sourceDir: string,
-  share: {[key: string]: TypeName}
-}
-*/
-
-function Y (opts/* :YOptions */) /* :Promise<YConfig> */ {
-  opts.types = opts.types != null ? opts.types : []
-  var modules = [opts.db.name, opts.connector.name].concat(opts.types)
-  for (var name in opts.share) {
-    modules.push(opts.share[name])
-  }
-  Y.sourceDir = opts.sourceDir
-  return new Promise(function (resolve, reject) {
-    setTimeout(function () {
-      Y.requestModules(modules).then(function () {
-        if (opts == null) reject('An options object is expected! ')
-        else if (opts.connector == null) reject('You must specify a connector! (missing connector property)')
-        else if (opts.connector.name == null) reject('You must specify connector name! (missing connector.name property)')
-        else if (opts.db == null) reject('You must specify a database! (missing db property)')
-        else if (opts.connector.name == null) reject('You must specify db name! (missing db.name property)')
-        else if (opts.share == null) reject('You must specify a set of shared types!')
-        else {
-          var yconfig = new YConfig(opts)
-          yconfig.db.whenUserIdSet(function () {
-            yconfig.init(function () {
-              resolve(yconfig)
-            })
-          })
-        }
-      }).catch(reject)
-    }, 0)
-  })
-}
-
-class YConfig {
-  /* ::
-  db: Y.AbstractDatabase;
-  connector: Y.AbstractConnector;
-  share: {[key: string]: any};
-  options: Object;
-  */
-  constructor (opts, callback) {
-    this.options = opts
-    this.db = new Y[opts.db.name](this, opts.db)
-    this.connector = new Y[opts.connector.name](this, opts.connector)
-  }
-  init (callback) {
-    var opts = this.options
-    var share = {}
-    this.share = share
-    this.db.requestTransaction(function * requestTransaction () {
-      // create shared object
-      for (var propertyname in opts.share) {
-        var typeConstructor = opts.share[propertyname].split('(')
-        var typeName = typeConstructor.splice(0, 1)
-        var args = []
-        if (typeConstructor.length === 1) {
-          try {
-            args = JSON.parse('[' + typeConstructor[0].split(')')[0] + ']')
-          } catch (e) {
-            throw new Error('Was not able to parse type definition! (share.' + propertyname + ')')
-          }
-        }
-        var type = Y[typeName]
-        var typedef = type.typeDefinition
-        var id = ['_', typedef.struct + '_' + typeName + '_' + propertyname + '_' + typeConstructor]
-        share[propertyname] = yield* this.createType(type.apply(typedef, args), id)
-      }
-      this.store.whenTransactionsFinished()
-        .then(callback)
-    })
-  }
-  isConnected () {
-    return this.connector.isSynced
-  }
-  disconnect () {
-    return this.connector.disconnect()
-  }
-  reconnect () {
-    return this.connector.reconnect()
-  }
-  destroy () {
-    if (this.connector.destroy != null) {
-      this.connector.destroy()
-    } else {
-      this.connector.disconnect()
-    }
-    var self = this
-    this.db.requestTransaction(function * () {
-      yield* self.db.destroy()
-      self.connector = null
-      self.db = null
-    })
-  }
-}
-
-if (typeof window !== 'undefined') {
-  window.Y = Y
-}

test/encode-decode.js

@@ -0,0 +1,62 @@
+import { test } from '../node_modules/cutest/cutest.mjs'
+import BinaryEncoder from '../src/Binary/Encoder.js'
+import BinaryDecoder from '../src/Binary/Decoder.js'
+import { generateUserID } from '../src/Util/generateUserID.js'
+import Chance from 'chance'
+
+function testEncoding (t, write, read, val) {
+  let encoder = new BinaryEncoder()
+  write(encoder, val)
+  let reader = new BinaryDecoder(encoder.createBuffer())
+  let result = read(reader)
+  t.log(`string encode: ${JSON.stringify(val).length} bytes / binary encode: ${encoder.data.length} bytes`)
+  t.compare(val, result, 'Compare results')
+}
+
+const writeVarUint = (encoder, val) => encoder.writeVarUint(val)
+const readVarUint = decoder => decoder.readVarUint()
+
+test('varUint 1 byte', async function varUint1 (t) {
+  testEncoding(t, writeVarUint, readVarUint, 42)
+})
+
+test('varUint 2 bytes', async function varUint2 (t) {
+  testEncoding(t, writeVarUint, readVarUint, 1 << 9 | 3)
+  testEncoding(t, writeVarUint, readVarUint, 1 << 9 | 3)
+})
+test('varUint 3 bytes', async function varUint3 (t) {
+  testEncoding(t, writeVarUint, readVarUint, 1 << 17 | 1 << 9 | 3)
+})
+
+test('varUint 4 bytes', async function varUint4 (t) {
+  testEncoding(t, writeVarUint, readVarUint, 1 << 25 | 1 << 17 | 1 << 9 | 3)
+})
+
+test('varUint of 2839012934', async function varUint2839012934 (t) {
+  testEncoding(t, writeVarUint, readVarUint, 2839012934)
+})
+
+test('varUint random', async function varUintRandom (t) {
+  const chance = new Chance(t.getSeed() * Math.pow(Number.MAX_SAFE_INTEGER))
+  testEncoding(t, writeVarUint, readVarUint, chance.integer({min: 0, max: (1 << 28) - 1}))
+})
+
+test('varUint random user id', async function varUintRandomUserId (t) {
+  t.getSeed() // enforces that this test is repeated
+  testEncoding(t, writeVarUint, readVarUint, generateUserID())
+})
+
+const writeVarString = (encoder, val) => encoder.writeVarString(val)
+const readVarString = decoder => decoder.readVarString()
+
+test('varString', async function varString (t) {
+  testEncoding(t, writeVarString, readVarString, 'hello')
+  testEncoding(t, writeVarString, readVarString, 'test!')
+  testEncoding(t, writeVarString, readVarString, '☺☺☺')
+  testEncoding(t, writeVarString, readVarString, '1234')
+})
+
+test('varString random', async function varStringRandom (t) {
+  const chance = new Chance(t.getSeed() * 1000000000)
+  testEncoding(t, writeVarString, readVarString, chance.string())
+})